Tüm alıştırma soruları

2789 soru

Soru 1101Soru

In many forest ecosystems, the complex symbiotic network of subterranean mycorrhizal fungi and tree roots facilitates the rapid exchange of carbon and nutrients across vast distances. However, a single thread of these fungal filaments, which can extend through meters of soil to connect distant saplings to the main grid, often remains isolated from ______ surrounding web.

Which choice completes the text so that it conforms to the conventions of Standard English?

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Cevap: its

Cevap

its
The correct answer is the singular possessive determiner 'its'. The pronoun must agree in number with its antecedent, the singular noun 'thread' (from the phrase 'a single thread of these fungal filaments'). Additionally, because the pronoun modifies the noun phrase 'surrounding web', the possessive case 'its' is required.

Adım Adım Çözüm

1
Identify the antecedent of the pronoun needed in the blank.
The antecedent is the singular noun 'thread' from the subject noun phrase 'a single thread of these fungal filaments'.
The sentence states that a single thread remains isolated from the surrounding web, so the pronoun must refer back to 'thread'.
2
Determine the required grammatical case for the pronoun.
A possessive determiner is required to modify the noun phrase 'surrounding web'.
The blank directly precedes and modifies the noun phrase 'surrounding web', indicating ownership or association.
3
Select the pronoun that matches both the singular number of the antecedent and the possessive case requirement.
The singular possessive determiner 'its' is the correct choice.
It correctly agrees with the singular, gender-neutral antecedent 'thread' and functions as a possessive determiner.

Anahtar Kavram

Pronoun-Antecedent Agreement and Case
Soru 1102Soru

A line in the coordinate plane is defined by the function f(x)=px+qf(x) = px + q, where pp and qq are constants. This line contains the point (6,2)(6, 2) and intersects the vertical axis at a point with a negative yy-coordinate. If the region bounded by the line and the two coordinate axes is a right triangle with an area of 2525, what is the value of pp?

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Cevap: 2

Cevap

2
The correct answer is the option representing the value 22. Substituting the point (6,2)(6, 2) into the linear function gives q=26pq = 2 - 6p. The area of the right triangle formed by the intercepts and the origin is given by 12×base×height=q22p\frac{1}{2} \times |\text{base}| \times |\text{height}| = \frac{q^2}{2p}. Setting this equal to 2525 leads to the quadratic equation 18p237p+2=018p^2 - 37p + 2 = 0. Factoring this equation yields p=2p = 2 or p=118p = \frac{1}{18}. Checking the yy-intercept condition (q<0q < 0) shows that only p=2p = 2 yields a negative yy-intercept (q=10q = -10), whereas p=118p = \frac{1}{18} yields a positive yy-intercept (q=53q = \frac{5}{3}).

Adım Adım Çözüm

1
Use the point (6,2)(6, 2) to express qq in terms of pp.
q=26pq = 2 - 6p
Since the line contains (6,2)(6, 2), substituting x=6x = 6 and f(x)=2f(x) = 2 into the function f(x)=px+qf(x) = px + q must satisfy the equation.
2
Determine the intercepts of the line on the coordinate axes.
The vertical intercept is (0,q)(0, q) and the horizontal intercept is (qp,0)\left(-\frac{q}{p}, 0\right).
The vertical intercept is found by setting x=0x = 0, and the horizontal intercept is found by setting f(x)=0f(x) = 0.
3
Express the area of the bounded right triangle and set it equal to 2525.
q22p=25q2=50p\frac{q^2}{2p} = 25 \Rightarrow q^2 = 50p
The area of a right triangle with vertices at the origin and the intercepts is 12×base×height=12(qp)(q)=q22p\frac{1}{2} \times |\text{base}| \times |\text{height}| = \frac{1}{2} \left(-\frac{q}{p}\right)(-q) = \frac{q^2}{2p}.
4
Substitute q=26pq = 2 - 6p into q2=50pq^2 = 50p and solve the quadratic equation.
18p237p+2=0(18p1)(p2)=0p=218p^2 - 37p + 2 = 0 \Rightarrow (18p - 1)(p - 2) = 0 \Rightarrow p = 2 or p=118p = \frac{1}{18}.
Substituting the expression for qq gives a quadratic equation in terms of pp that can be factored to find its roots.
5
Verify which root satisfies the condition that the vertical intersection point has a negative yy-coordinate.
For p=2p = 2, q=10q = -10 (valid). For p=118p = \frac{1}{18}, q=53q = \frac{5}{3} (invalid). Thus, p=2p = 2.
The problem states that the vertical axis intersection (yy-intercept) must have a negative yy-coordinate (q<0q < 0).

Anahtar Kavram

Using coordinate points and geometric properties of intercepts to determine parameters of linear functions
Soru 1103Soru

In the xyxy-plane, the graph of a linear function ff has a negative slope and a positive yy-intercept. The graph of ff intersects the xx-axis at point AA and the yy-axis at point BB. A second line, LL, is perpendicular to the graph of ff and passes through the origin. If line LL intersects the graph of ff at point PP such that the ratio of the area of triangle OAPOAP to the area of triangle OBPOBP is 4:94:9, what is the slope of the graph of ff?

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Cevap: 32-\frac{3}{2}

Cevap

The slope of the graph of ff is 32-\frac{3}{2}.
The correct answer is 32-\frac{3}{2}. By setting up the equations of the lines f(x)=mx+bf(x) = mx + b and y=1mxy = -\frac{1}{m}x, we can express the coordinates of the intercepts AA and BB, as well as the intersection point PP, in terms of mm and bb. Calculating the areas of triangle OAPOAP and triangle OBPOBP gives Area(OAP)=12(bm)y0\text{Area}(OAP) = \frac{1}{2} \left(-\frac{b}{m}\right) y_0 and Area(OBP)=12bx0\text{Area}(OBP) = \frac{1}{2} b x_0. Since PP lies on the perpendicular line, y0=1mx0y_0 = -\frac{1}{m}x_0. Substituting this into the area ratio yields Area(OAP)Area(OBP)=1m2\frac{\text{Area}(OAP)}{\text{Area}(OBP)} = \frac{1}{m^2}. Equating this to the given ratio 49\frac{4}{9} results in m2=94m^2 = \frac{9}{4}. Given that the slope is negative, mm must be 32-\frac{3}{2}.

Adım Adım Çözüm

1
Define the linear function f(x)f(x) and the line LL perpendicular to it.
Let the function be f(x)=mx+bf(x) = mx + b, where m<0m < 0 and b>0b > 0. The line LL perpendicular to the graph of ff that passes through the origin has the equation y=1mxy = -\frac{1}{m}x.
This establishes the equations of both lines in terms of the slope mm and yy-intercept bb.
2
Determine the coordinates of the intercepts AA and BB, and the intersection point P(x0,y0)P(x_0, y_0).
The xx-intercept is A(bm,0)A\left(-\frac{b}{m}, 0\right) and the yy-intercept is B(0,b)B(0, b). The intersection point P(x0,y0)P(x_0, y_0) is the solution to mx+b=1mxmx + b = -\frac{1}{m}x, which gives x0=mbm2+1x_0 = -\frac{mb}{m^2+1} and y0=bm2+1y_0 = \frac{b}{m^2+1}.
Finding these points allows us to express the dimensions of triangles OAPOAP and OBPOBP.
3
Calculate the areas of triangles OAPOAP and OBPOBP and find their ratio in terms of mm.
The base of triangle OAPOAP along the xx-axis is OA=bmOA = -\frac{b}{m} and its height is y0y_0. Thus, Area(OAP)=12(bm)y0\text{Area}(OAP) = \frac{1}{2} \left(-\frac{b}{m}\right) y_0. The base of triangle OBPOBP along the yy-axis is OB=bOB = b and its height is x0x_0. Thus, Area(OBP)=12bx0\text{Area}(OBP) = \frac{1}{2} b x_0. The ratio of their areas is Area(OAP)Area(OBP)=bmy0bx0=y0mx0\frac{\text{Area}(OAP)}{\text{Area}(OBP)} = \frac{-\frac{b}{m} y_0}{b x_0} = -\frac{y_0}{m x_0}. Since PP lies on LL, we have y0x0=1m\frac{y_0}{x_0} = -\frac{1}{m}. Substituting this gives the ratio Area(OAP)Area(OBP)=1m(1m)=1m2\frac{\text{Area}(OAP)}{\text{Area}(OBP)} = -\frac{1}{m}\left(-\frac{1}{m}\right) = \frac{1}{m^2}.
This simplifies the geometric relationship to a direct relation between the area ratio and the slope of the function.
4
Solve for the slope mm using the given ratio of 4:94:9.
Setting 1m2=49\frac{1}{m^2} = \frac{4}{9} yields m2=94m^2 = \frac{9}{4}. Since the problem states the slope is negative, we take the negative square root to get m=32m = -\frac{3}{2}.
This identifies the correct slope value matching the given constraints.

Anahtar Kavram

Using coordinate geometry and system of linear equations to determine slopes and intersections, and relating those to geometric areas on the coordinate plane.
Soru 1104Soru

Read the passage below. Based on the rules of Standard English conventions, which punctuation mark must fill the blank to correctly set off the nonessential element?

Aşağıdaki boşlukları doldurun

In 1735, the self-taught English clockmaker John Harrison presented his first marine chronometer—a revolutionary timekeeping device designed to accurately calculate longitude at seato the British Board of Longitude. Harrison’s ingenious invention solved a monumental navigation problem that had baffled scientists for centuries, enabling sailors to safely navigate the open ocean by determining their precise east-west position.
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Cevap

An em dash (—)
The correct punctuation mark is an em dash because the nonessential appositive phrase 'a revolutionary timekeeping device designed to accurately calculate longitude at sea' is opened with an em dash. Under Standard English conventions, nonessential elements must be set off with matching pairs of punctuation (comma-comma, dash-dash, or parenthesis-parenthesis). Thus, an em dash must be used to close the phrase to maintain punctuation symmetry.

Adım Adım Çözüm

1
Identify the nonessential element in the sentence.
The phrase 'a revolutionary timekeeping device designed to accurately calculate longitude at sea' is determined to be an appositive phrase that provides nonessential descriptive details about the 'marine chronometer'.
Identifying the nonessential element is necessary to determine where punctuation boundaries must be established.
2
Examine the punctuation mark used to open the nonessential element.
An em dash ('—') is used immediately after 'chronometer' to introduce the appositive phrase.
Standard English conventions require that nonessential elements be set off from the rest of the sentence using a matching pair of punctuation marks.
3
Determine the correct punctuation mark to close the nonessential element.
An em dash ('—') must be placed in the blank before 'to the British Board' to match the opening em dash.
Using any other punctuation mark would violate the rule of punctuation symmetry.

Anahtar Kavram

Punctuation of Nonessential Elements
Soru 1105Soru

In her analysis of Homer's *Odyssey*, classicist Emily Wilson highlights how the narrative frequently shifts between the perspectives of elite heroes and marginalized figures. Wilson argues that while the former group's members dominate the poem's formal speeches, the other ______ quiet observations provide a crucial counter-narrative, offering a critique of the rigid social hierarchy that governs ancient Ithaca.

Which choice completes the text so that it conforms to the conventions of Standard English?

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Cevap: characters'

Cevap

characters'
The correct answer is the plural possessive noun 'characters''. In the sentence, the word in the blank modifies the noun 'observations' to indicate who is observing, requiring a possessive form. The context refers back to the plural 'marginalized figures,' indicating that a plural possessive noun is needed. For plural nouns ending in 's,' the possessive is formed by adding an apostrophe after the 's.'

Adım Adım Çözüm

1
Identify the noun that the blank word modifies and determine if possession is required.
The word in the blank modifies the noun 'observations'. Because the observations belong to the other characters in the narrative, a possessive form is necessary.
Possessive nouns are used to indicate ownership or association with a following noun.
2
Determine whether the possessive noun should be singular or plural based on the context.
The blank refers back to 'marginalized figures', which is a plural noun phrase.
The grammatical number of the possessive noun must agree with its plural antecedent.
3
Combine the plural and possessive requirements to select the correct spelling and punctuation.
The plural of 'character' is 'characters', and its possessive form is created by adding an apostrophe after the 's' ('characters'').
Plural nouns ending in 's' form the possessive by adding only an apostrophe.

Anahtar Kavram

Plural and Possessive Nouns
Soru 1106Soru

A project manager uses the linear equation ax+by=cax + by = c to model the allocation of resources, where xx represents the number of hours spent on research, yy represents the number of hours spent on development, and a,b,a, b, and cc are positive constants. Initially, the project manager allocates 4040 hours for research and 3030 hours for development. To optimize the project, the manager decides to increase the research hours by 25%25\% and decrease the development hours by 20%20\% such that the total resource value, cc, remains unchanged. Which of the following equations correctly expresses aa in terms of bb?

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Cevap: a=0.6ba = 0.6b

Cevap

The equation a=0.6ba = 0.6b correctly expresses aa in terms of bb.
The correct equation is a=0.6ba = 0.6b. The initial resource allocation is represented by 40a+30b=c40a + 30b = c. Increasing 4040 by 25%25\% gives 5050, and decreasing 3030 by 20%20\% gives 2424, which yields the new equation 50a+24b=c50a + 24b = c. Equating these two expressions since cc is constant gives 40a+30b=50a+24b40a + 30b = 50a + 24b. Simplifying this equation results in 6b=10a6b = 10a, which gives a=0.6ba = 0.6b.

Adım Adım Çözüm

1
Write the linear equation representing the initial allocation of resources.
40a+30b=c40a + 30b = c
The initial values are 4040 hours for research (xx) and 3030 hours for development (yy).
2
Calculate the new values of xx and yy after the percentage changes are applied.
x=40×1.25=50x = 40 \times 1.25 = 50 and y=30×0.80=24y = 30 \times 0.80 = 24
Research hours increase by 25%25\% and development hours decrease by 20%20\%.
3
Write the new linear equation with the updated resource allocations.
50a+24b=c50a + 24b = c
The total resource value cc remains unchanged.
4
Equate the two expressions for cc and solve for aa in terms of bb.
40a+30b=50a+24b    6b=10a    a=0.6b40a + 30b = 50a + 24b \implies 6b = 10a \implies a = 0.6b
Since both equations equal the same constant cc, we set them equal to each other and isolate the variable aa.

Anahtar Kavram

Expressing and manipulating linear relationships in two variables with constraints.

Alternatif Yöntem

Instead of keeping cc general, we can choose a convenient value for cc, such as c=120c = 120. This gives two linear equations in terms of aa and bb: 40a+30b=12040a + 30b = 120 and 50a+24b=12050a + 24b = 120. Solving this system for the ratio of aa to bb yields a=1.33a = 1.33 and b=2.22b = 2.22, which confirms that a/b=0.6a/b = 0.6, or a=0.6ba = 0.6b.
Tahmini Süre:3m 0s
Soru 1107Soru

In his analysis of ancient Mediterranean trade networks, historian Marcus Aureli examines the economic motivations of early merchants. He argues that the rapid expansion of maritime routes during the late Roman Republic was driven not only by a growing domestic demand for exotic agricultural goods but also ______ stronger diplomatic ties with eastern provinces.

Which choice completes the text so that it conforms to the conventions of Standard English?

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Cevap: by a strategic effort to establish

Cevap

by a strategic effort to establish
The correct answer maintains parallel structure by using a prepositional phrase starting with the preposition 'by' ('by a strategic effort to establish'). This matches the structure of the first element in the correlative conjunction 'not only... but also,' which is 'by a growing domestic demand for exotic agricultural goods.'

Adım Adım Çözüm

1
Identify the grammatical construction and the parallel elements in the sentence.
The sentence uses the correlative conjunction structure 'not only... but also.'
This correlative conjunction requires that the elements following 'not only' and 'but also' be grammatically parallel.
2
Determine the grammatical form of the first element.
The phrase following 'not only' is 'by a growing domestic demand for exotic agricultural goods,' which is a prepositional phrase starting with the preposition 'by.'
This establishes that the element following 'but also' must also be a prepositional phrase starting with 'by' to maintain parallel structure.
3
Evaluate the choices to find the one that matches this grammatical structure.
The phrase 'by a strategic effort to establish' begins with the preposition 'by' followed by a noun phrase, matching the structure of the first element.
Only this option correctly maintains the prepositional phrase structure required for parallelism in this sentence.

Anahtar Kavram

Parallel Structure with Correlative Conjunctions
Tahmini Süre:1m 0s
Soru 1108Soru

A student tracks the remaining battery percentage, yy, of a tablet after xx hours of use. The table below shows the battery percentage at three different times:

Time (xx, hours)Battery percentage (yy)
090
375
660

Which of the following equations represents the relationship between xx and yy?

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Cevap: y=5x+90y = -5x + 90

Cevap

y = -5x + 90
The correct equation is y=5x+90y = -5x + 90. According to the table, when time x=0x = 0, the battery percentage y=90y = 90, which indicates that the y-intercept of the line is 9090. The slope can be determined using any two points from the table, such as (0,90)(0, 90) and (3,75)(3, 75): slope=759030=153=5\text{slope} = \frac{75 - 90}{3 - 0} = \frac{-15}{3} = -5. Writing this in slope-intercept form gives y=5x+90y = -5x + 90.

Adım Adım Çözüm

1
Identify the y-intercept from the table.
The y-intercept bb is 9090.
When the time x=0x = 0 hours, the battery percentage y=90y = 90. This corresponds to the y-intercept of the linear equation.
2
Calculate the slope (rate of change) using two points from the table.
The slope mm is 5-5.
Using the points (0,90)(0, 90) and (3,75)(3, 75), the slope is calculated as the change in yy divided by the change in xx: m=759030=153=5m = \frac{75 - 90}{3 - 0} = \frac{-15}{3} = -5.
3
Substitute the slope and y-intercept into the slope-intercept form equation.
y=5x+90y = -5x + 90
Plugging m=5m = -5 and b=90b = 90 into y=mx+by = mx + b yields the final equation.

Anahtar Kavram

Determining a linear equation in two variables from a table of values.
Tahmini Süre:1m 0s
Soru 1109Soru

In 1977, oceanographers exploring the Galapagos Rift made a startling discovery: deep-sea hydrothermal vents teeming with previously unknown life. Before this historic expedition, scientists _______ that life could not exist in the deep ocean without sunlight to power photosynthesis.

Which choice completes the text so that it conforms to the conventions of Standard English?

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Cevap: had believed

Cevap

had believed
The correct option is 'had believed'. The passage describes a series of events in the past: the oceanographers' expedition and discovery occurred in 1977 ('made'). The sentence with the blank describes a belief held by scientists prior to that past expedition ('Before this historic expedition'). To express an action or state that was completed before another past event, standard English conventions require the past perfect tense, which is formed using 'had' followed by the past participle ('had believed').

Adım Adım Çözüm

1
Identify the timeline of events in the passage.
The passage establishes that oceanographers made a discovery in 1977 ('made'), which is in the simple past tense.
Establishing the temporal anchor helps determine the relationship of other verbs in the sentence.
2
Analyze the relationship between the blank and the past events.
The blank describes a belief ('scientists _______ that life could not exist') that occurred and was completed prior to the 1977 expedition ('Before this historic expedition').
Understanding the sequence of events is crucial for choosing the correct verb aspect.
3
Select the appropriate verb tense and aspect.
To describe a state or action that occurred before another action in the past, the past perfect tense ('had' + past participle) is required. Therefore, 'had believed' is the correct form.
Conforming to standard English conventions requires the past perfect aspect for past-of-the-past relationships.

Anahtar Kavram

Verb Tense, Aspect, and Mood
Tahmini Süre:1m 0s
Soru 1110Soru

If the equation 34(8x12)56(6x18)=12(4x8)\frac{3}{4}(8x - 12) - \frac{5}{6}(6x - 18) = -\frac{1}{2}(4x - 8) is true, what is the value of xx?

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Cevap: 23-\frac{2}{3}

Cevap

23-\frac{2}{3}
The correct answer is found by distributing the coefficients across each set of parentheses, combining like terms on the left side to get x+6=2x+4x + 6 = -2x + 4, adding 2x2x to both sides to get 3x+6=43x + 6 = 4, subtracting 66 from both sides to get 3x=23x = -2, and finally dividing by 33 to obtain 23-\frac{2}{3}.

Adım Adım Çözüm

1
Distribute the coefficients to the terms inside the parentheses on both sides of the equation.
6x95x+15=2x+46x - 9 - 5x + 15 = -2x + 4
To eliminate the parentheses and prepare the equation for combining like terms.
2
Combine the constant and variable terms on the left side of the equation.
x+6=2x+4x + 6 = -2x + 4
To simplify the left side of the equation.
3
Add 2x2x to both sides of the equation.
3x+6=43x + 6 = 4
To group all terms containing the variable xx on the left side.
4
Subtract 66 from both sides, then divide by 33 to solve for xx.
3x=23x = -2, which gives x=23x = -\frac{2}{3}
To isolate xx and find its value.

Anahtar Kavram

Linear Equations in One Variable
Soru 1111Soru

For the linear function ff, the value of f(0)f(0) is 33 and the value of f(5)f(5) is 1818. What is the slope of the graph of y=f(x)y = f(x) in the xyxy-plane?

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Cevap: 3

Cevap

The slope of the graph of y=f(x)y = f(x) is 33.
The slope of a linear function can be determined using any two points (x1,y1)(x_1, y_1) and (x2,y2)(x_2, y_2) on its graph with the formula m=y2y1x2x1m = \frac{y_2 - y_1}{x_2 - x_1}. The given function values f(0)=3f(0) = 3 and f(5)=18f(5) = 18 correspond to the coordinate points (0,3)(0, 3) and (5,18)(5, 18) respectively. Substituting these coordinates into the formula gives m=18350=155=3m = \frac{18 - 3}{5 - 0} = \frac{15}{5} = 3.

Adım Adım Çözüm

1
Identify the coordinates of two points on the line using the given function values.
The function values f(0)=3f(0) = 3 and f(5)=18f(5) = 18 correspond to the points (0,3)(0, 3) and (5,18)(5, 18) on the graph of the function.
In function notation, f(x)=yf(x) = y represents a point (x,y)(x, y) on the graph of the function.
2
Calculate the slope using the slope formula.
The slope mm is calculated as 18350=3\frac{18 - 3}{5 - 0} = 3.
The slope of a line is defined as the change in yy divided by the change in xx between any two points on the line.

Anahtar Kavram

Calculating the slope of a linear function from given function values.
Soru 1112Soru

While botanical expeditions in Borneo have revealed that each of the newly cataloged species of carnivorous pitcher plants displays highly specialized physical adaptations to capture prey, ______ long-term survival in the nutrient-poor soil of the tropical rainforest remains dependent on a delicate symbiotic relationship with mutualistic ants.

Which choice completes the text so that it conforms to the conventions of Standard English?

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Cevap: its

Cevap

The singular possessive pronoun 'its' correctly refers to the singular antecedent 'each'.
The singular possessive pronoun 'its' correctly agrees with the singular antecedent 'each'. In standard English, indefinite pronouns such as 'each' are grammatically singular, and their grammatical number is not affected by intervening plural prepositional phrases like 'of the newly cataloged species of carnivorous pitcher plants'.

Adım Adım Çözüm

1
Locate the antecedent of the pronoun needed for the blank.
The antecedent is the singular indefinite pronoun 'each' at the start of the clause.
Pronouns must match the grammatical number of their antecedents.
2
Analyze the role of intervening phrases to avoid agreement errors.
The plural nouns 'species' and 'plants' are objects of prepositional phrases and do not change the singular nature of the subject 'each'.
Intervening prepositional phrases should not affect the pronoun-antecedent agreement.
3
Identify the required case and form for the blank.
The blank modifies the noun 'survival', indicating a singular possessive pronoun is required.
The singular possessive pronoun 'its' is the only form that is grammatically correct and matches the singular antecedent.

Anahtar Kavram

Pronoun-Antecedent Agreement and Case
Soru 1113Soru

If 3(2.5x4)1.5(x2)=0.8(5x+10)3(2.5x - 4) - 1.5(x - 2) = 0.8(5x + 10), what is the value of xx?

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Cevap: 8.5

Cevap

8.5
By distributing and simplifying terms, the linear equation simplifies to 2x=172x = 17, which yields x=8.5x = 8.5.

Adım Adım Çözüm

1
Distribute the constants on both sides of the equation.
7.5x121.5x+3=4x+87.5x - 12 - 1.5x + 3 = 4x + 8
To simplify the expressions.
2
Combine like terms on the left side.
6x9=4x+86x - 9 = 4x + 8
To simplify the left side of the equation.
3
Subtract 4x4x from both sides of the equation.
2x9=82x - 9 = 8
To group variable terms on one side.
4
Add 9 to both sides of the equation.
2x=172x = 17
To isolate the term with the variable.
5
Divide both sides by 2.
x=8.5x = 8.5
To find the final value of the variable.

Anahtar Kavram

Linear Equations in One Variable

Alternatif Yöntem

Multiply the entire equation by 10 to clear all decimal values: 30(2.5x4)15(x2)=8(5x+10)30(2.5x - 4) - 15(x - 2) = 8(5x + 10). Expanding this yields 75x12015x+30=40x+8075x - 120 - 15x + 30 = 40x + 80, which simplifies to 60x90=40x+8060x - 90 = 40x + 80. Subtracting 40x40x and adding 90 to both sides gives 20x=17020x = 170, resulting in x=8.5x = 8.5.
Tahmini Süre:1m 30s
Soru 1114Soru

In many songbird species, juvenile males acquire their unique songs by imitating adult tutors during a critical, time-limited developmental window. Young zebra finches, for example, must be exposed to tutor songs within their first eighty days of _______ they will fail to develop the complex, species-typical vocalizations required for successful courtship.

Which choice completes the text so that it conforms to the conventions of Standard English?

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Cevap: life; otherwise,

Cevap

The correct choice is the option containing 'life; otherwise,' because it uses a semicolon to connect two independent clauses, followed by the conjunctive adverb 'otherwise' and a comma.
The correct choice is the option containing 'life; otherwise,' because it properly links the two independent clauses. A semicolon is used to separate the independent clauses, and the conjunctive adverb 'otherwise' is followed by a comma to establish the consequential relationship between the clauses.

Adım Adım Çözüm

1
Analyze the structure of the text surrounding the blank to identify the boundary between the clauses.
The text contains two independent clauses: 'Young zebra finches, for example, must be exposed to tutor songs within their first eighty days of life' and 'they will fail to develop the complex, species-typical vocalizations required for successful courtship.'
Identifying that both clauses can stand alone as complete sentences helps determine the correct punctuation or coordinating conjunction needed to link them.
2
Determine the logical relationship between the two independent clauses.
The second clause describes the negative consequence of failing to meet the condition stated in the first clause. The transition needs to mean 'if not' or 'or else'.
This establishes that a transitional word expressing consequence or negative condition, such as 'otherwise', is semantically necessary.
3
Select the option that conforms to standard English conventions for joining independent clauses with a conjunctive adverb.
The option using a semicolon followed by 'otherwise' and a comma correctly avoids a comma splice or run-on sentence.
Two independent clauses joined by a conjunctive adverb must be separated by a semicolon (or a period) before the adverb, typically followed by a comma.

Anahtar Kavram

Joining independent clauses using a semicolon and a conjunctive adverb.
Soru 1115Soru

A linear function ff is defined by f(x)=mx+bf(x) = mx + b, where mm and bb are constants. The graph of ff in the xyxy-plane passes through the point (2,5)(2, 5). A second linear function gg is defined by g(x)=f(x3)+4g(x) = f(x - 3) + 4. The graph of gg has an xx-intercept of (k,0)(k, 0) and a yy-intercept of (0,k)(0, -k), where kk is a nonzero constant. What is the value of f(8)f(8)?

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Cevap: 11

Cevap

11
The correct answer is 11. By using the given point on the graph of f(x)f(x), we express its y-intercept bb in terms of its slope mm as b=52mb = 5 - 2m. Substituting this expression into the translation equation g(x)=f(x3)+4g(x) = f(x - 3) + 4 yields g(x)=mx5m+9g(x) = mx - 5m + 9. Setting the y-intercept of g(x)g(x), which is 5m+9-5m + 9, equal to k-k gives k=5m9k = 5m - 9. Evaluating g(x)g(x) at its x-intercept x=kx = k gives mk5m+9=0mk - 5m + 9 = 0. Substituting the relation 5m+9=k-5m + 9 = -k into this equation yields mkk=0mk - k = 0, or k(m1)=0k(m - 1) = 0. Since kk is nonzero, we find m=1m = 1, which in turn gives b=3b = 3. Thus, the linear function is f(x)=x+3f(x) = x + 3, and f(8)=11f(8) = 11.

Adım Adım Çözüm

1
Express the y-intercept constant bb in terms of the slope mm.
b=52mb = 5 - 2m
Since the graph of f(x)=mx+bf(x) = mx + b passes through (2,5)(2, 5), substituting x=2x = 2 and f(x)=5f(x) = 5 gives 5=2m+b5 = 2m + b.
2
Write the expression for g(x)g(x) in terms of mm.
g(x)=mx5m+9g(x) = mx - 5m + 9
By definition, g(x)=f(x3)+4=m(x3)+b+4g(x) = f(x - 3) + 4 = m(x - 3) + b + 4. Substituting b=52mb = 5 - 2m simplifies the expression to g(x)=mx5m+9g(x) = mx - 5m + 9.
3
Relate the y-intercept of g(x)g(x) to the parameter kk.
k=5m9k = 5m - 9
The y-intercept of g(x)g(x) is g(0)=5m+9g(0) = -5m + 9. Since the y-intercept is given as (0,k)(0, -k), we set k=5m+9-k = -5m + 9, which gives k=5m9k = 5m - 9.
4
Set up an equation using the x-intercept of g(x)g(x).
g(k)=mk5m+9=0g(k) = mk - 5m + 9 = 0
Since the x-intercept of g(x)g(x) is (k,0)(k, 0), substituting x=kx = k into the expression for g(x)g(x) must yield 00.
5
Solve for the slope mm.
m=1m = 1
Substituting 5m+9=k-5m + 9 = -k into the equation mk5m+9=0mk - 5m + 9 = 0 gives mkk=0mk - k = 0, which factors as k(m1)=0k(m - 1) = 0. Since kk is a nonzero constant, we divide by kk to get m1=0m - 1 = 0, so m=1m = 1.
6
Find the constant bb and write the final formula for f(x)f(x).
f(x)=x+3f(x) = x + 3
Substituting m=1m = 1 back into b=52mb = 5 - 2m yields b=3b = 3. Therefore, f(x)=x+3f(x) = x + 3.
7
Evaluate f(8)f(8).
11
Substituting x=8x = 8 into the function f(x)=x+3f(x) = x + 3 gives f(8)=8+3=11f(8) = 8 + 3 = 11.

Anahtar Kavram

Linear function transformations and intercept properties
Soru 1116Soru

Complete the passage with the form of the verb 'publish' that correctly completes the sentence to conform to the conventions of Standard English.

Aşağıdaki boşlukları doldurun

While studying Maya hieroglyphs in the 1950s, art historian Tatiana Proskouriakoff noticed patterns of dates that corresponded to the lifespans of historic rulers. Before Proskouriakoff her breakthrough, most scholars in the field of Mesoamerican archaeology had assumed that the glyphs represented only abstract astronomical or religious concepts, rather than records of historical events.
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Cevap

published
The correct answer is 'published' because the sentence describes a sequence of two past events. The action of scholars assuming the glyphs were abstract occurred before Proskouriakoff's breakthrough. Because the earlier action is marked by the past perfect verb 'had assumed', the subsequent past action (the breakthrough) must be expressed in the simple past tense ('published') to establish the correct chronological relationship.

Adım Adım Çözüm

1
Identify the relationship between the two events in the sentence: the scholars' assumption and Proskouriakoff's breakthrough.
The sentence outlines a clear chronological order between two past events.
Establishing the sequence of events determines the correct verb tense relationship.
2
Analyze the verb tense of the earlier event in the timeline.
The earlier action of the scholars' assumption is written in the past perfect tense ('had assumed').
The past perfect tense is used for an action completed before another past action.
3
Select the correct tense for the subsequent event (the breakthrough).
The subsequent past action must be written in the simple past tense ('published').
The simple past tense is required to show that the breakthrough occurred after the period when the scholars assumed otherwise.

Anahtar Kavram

Verb Tense, Aspect, and Mood
Soru 1117Soru

The equation 3x+4y=363x + 4y = 36 represents the relationship between the number of small boxes, xx, and large boxes, yy, that can fit in a delivery van. If the van is loaded with exactly 6 large boxes, what is the number of small boxes that can also fit in the van?

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Cevap: 4

Cevap

The number of small boxes that can also fit in the van is 4.
Substituting y=6y = 6 into the equation 3x+4y=363x + 4y = 36 gives 3x+24=363x + 24 = 36. Subtracting 24 from both sides results in 3x=123x = 12. Dividing both sides by 3 yields x=4x = 4. Thus, the number of small boxes that can fit is 4.

Adım Adım Çözüm

1
Substitute 6 for yy in the equation 3x+4y=363x + 4y = 36.
3x+4(6)=363x + 4(6) = 36
The variable yy represents the number of large boxes, which is given as 6.
2
Simplify the multiplication in the equation.
3x+24=363x + 24 = 36
To simplify the terms before solving for xx.
3
Subtract 24 from both sides of the equation.
3x=123x = 12
To isolate the variable term 3x3x on one side of the equation.
4
Divide both sides of the equation by 3.
x=4x = 4
To solve for xx, the number of small boxes.

Anahtar Kavram

Evaluating and solving a linear equation in two variables given the value of one variable.
Tahmini Süre:45s
Soru 1118Soru

The graph of the linear function ff in the xyxy-plane is defined by f(x)=kx+4f(x) = kx + 4, where kk is a positive constant. The graph of the linear function gg is obtained by translating the graph of ff left by 33 units and down by 22 units. If the xx-intercept of the graph of gg is 55 times the xx-intercept of the graph of ff, what is the value of kk?

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Cevap: 6

Cevap

6
The correct answer is 6. The linear function g(x)g(x) represents the translated graph, which is expressed as g(x)=f(x+3)2g(x) = f(x+3) - 2. Substituting f(x)=kx+4f(x) = kx + 4 yields g(x)=k(x+3)+42=kx+3k+2g(x) = k(x+3) + 4 - 2 = kx + 3k + 2. The xx-intercept of a graph is the point where the function value is 00. Solving f(x)=0f(x) = 0 gives the xx-intercept of the graph of ff as x=4kx = -\frac{4}{k}. Solving g(x)=0g(x) = 0 gives the xx-intercept of the graph of gg as x=3k+2kx = -\frac{3k + 2}{k}. We are given that the xx-intercept of the graph of gg is 55 times the xx-intercept of the graph of ff, which translates to the equation 3k+2k=5(4k)-\frac{3k+2}{k} = 5 \left(-\frac{4}{k}\right). Multiplying both sides by k-k (since k>0k > 0, k0k \neq 0) yields 3k+2=203k + 2 = 20. Subtracting 22 from both sides gives 3k=183k = 18, and dividing by 33 results in k=6k = 6.

Adım Adım Çözüm

1
Determine the equation of the translated function g(x)g(x)
g(x)=kx+3k+2g(x) = kx + 3k + 2
Shifting the graph of f(x)f(x) left by 33 units and down by 22 units translates to g(x)=f(x+3)2g(x) = f(x+3) - 2.
2
Find the xx-intercept of the graph of ff
x=4kx = -\frac{4}{k}
The xx-intercept is the input value for which the output of the function is zero, so we solve f(x)=0f(x) = 0.
3
Find the xx-intercept of the graph of gg
x=3k+2kx = -\frac{3k + 2}{k}
We set the equation of g(x)g(x) to zero and solve for xx in terms of kk.
4
Set up and solve the equation relating the two xx-intercepts
k=6k = 6
Using the relation xg=5xfx_g = 5 \cdot x_f, we obtain 3k+2k=5(4k)-\frac{3k + 2}{k} = 5 \left(-\frac{4}{k}\right), which simplifies to 3k+2=203k + 2 = 20, leading to k=6k = 6.

Anahtar Kavram

Function translations and finding intercepts of linear equations
Soru 1119Soru

The sentence below is missing a punctuation mark. What punctuation mark should be placed in the blank to correctly join the two independent clauses?

Aşağıdaki boşlukları doldurun

The novel was written in the nineteenth century nevertheless, its themes of social justice remain highly relevant to readers today.
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Cevap

A semicolon (;) is the correct punctuation mark to join the two independent clauses before the conjunctive adverb.
A semicolon is the correct punctuation mark because it is used to connect two independent clauses, especially when the second clause begins with a conjunctive adverb like 'nevertheless'.

Adım Adım Çözüm

1
Identify the clauses on either side of the blank.
The clause 'The novel was written in the nineteenth century' and the clause 'nevertheless, its themes of social justice remain highly relevant to readers today' are both independent clauses.
Determining if the clauses are independent is necessary to select the appropriate punctuation.
2
Identify the transition word starting the second clause.
The second clause starts with the transition word (conjunctive adverb) 'nevertheless'.
Transition words dictate specific punctuation requirements when joining independent clauses.
3
Apply the correct punctuation rule for joining independent clauses with a transition word.
A semicolon (;) must be placed before 'nevertheless' to correctly link the two clauses.
A semicolon is required to separate two independent clauses when the second begins with a conjunctive adverb.

Anahtar Kavram

Semicolons with conjunctive adverbs
Soru 1120Soru

In the xyxy-plane, a line with a positive slope mm and a yy-intercept of (0,b)(0, b) passes through the point (b,12)(b, 12), where b>0b > 0. If the area of the triangle bounded by the line, the xx-axis, and the yy-axis is 44, what is the value of mm?

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Cevap: 2

Cevap

2
The line equation is y=mx+by = mx + b. Substituting the point (b,12)(b, 12) gives 12=b(m+1)12 = b(m + 1). The xx-intercept of the line is at (bm,0)(-\frac{b}{m}, 0), which gives a base length of bm\frac{b}{m} for the right triangle, while the height is bb. The area of the triangle is b22m=4    b2=8m\frac{b^2}{2m} = 4 \implies b^2 = 8m. Substituting b=12m+1b = \frac{12}{m + 1} into this equation yields 144(m+1)2=8m    m(m+1)2=18\frac{144}{(m + 1)^2} = 8m \implies m(m + 1)^2 = 18. Solving this for positive values of mm gives the unique solution m=2m = 2.

Adım Adım Çözüm

1
Express the line equation and substitute the given point (b,12)(b, 12).
b(m+1)=12b(m + 1) = 12
Since the line has a yy-intercept of (0,b)(0, b) and a slope of mm, its equation is y=mx+by = mx + b. Substituting the point (b,12)(b, 12) yields 12=m(b)+b=b(m+1)12 = m(b) + b = b(m + 1).
2
Determine the lengths of the base and height of the triangle formed by the line and the coordinate axes.
Base =bm= \frac{b}{m}, Height =b= b
The yy-intercept is at (0,b)(0, b) and the xx-intercept is at (bm,0)(-\frac{b}{m}, 0). Since b>0b > 0 and m>0m > 0, the height is bb and the base is the absolute value of the xx-intercept, which is bm\frac{b}{m}.
3
Write the area equation of the triangle and simplify it.
b2=8mb^2 = 8m
The area of the right triangle is 12×base×height=12(bm)b=b22m\frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2} \left(\frac{b}{m}\right)b = \frac{b^2}{2m}. Setting this equal to the given area of 44 gives b22m=4    b2=8m\frac{b^2}{2m} = 4 \implies b^2 = 8m.
4
Solve the system of equations for mm.
m=2m = 2
Substituting b=12m+1b = \frac{12}{m + 1} into b2=8mb^2 = 8m yields (12m+1)2=8m    144(m+1)2=8m    m(m+1)2=18\left(\frac{12}{m + 1}\right)^2 = 8m \implies \frac{144}{(m + 1)^2} = 8m \implies m(m + 1)^2 = 18. Since m(m+1)2m(m + 1)^2 is strictly increasing for positive mm, testing small integers shows 2(3)2=182(3)^2 = 18, so m=2m = 2 is the unique positive real solution.

Anahtar Kavram

Formulating linear equations in slope-intercept form and solving non-linear systems of equations derived from geometric constraints.

Alternatif Yöntem

Instead of algebraically expanding the cubic equation, one can test small positive integers for mm in the equation m(m+1)2=18m(m + 1)^2 = 18. Testing m=1m = 1 yields 1(2)2=41(2)^2 = 4 (too small), and testing m=2m = 2 yields 2(3)2=182(3)^2 = 18 (correct). Because m(m+1)2m(m + 1)^2 is strictly increasing for m>0m > 0, m=2m = 2 is the only positive real root.
Tahmini Süre:3m 0s
ÖncekiSayfa 56 / 140Sonraki
Tüm alıştırma soruları — SAT | Examkin