Tüm alıştırma soruları

2789 soru

Soru 1201Soru

In the xyxy-plane, the graph of the linear function ff passes through the point (2,5)(2, 5) and has a yy-intercept of (0,b)(0, b), where bb is a constant. The function gg is defined by g(x)=f(x)4g(x) = f(x) - 4. If the xx-intercept of the graph of gg is (6,0)(6, 0), what is the value of bb?

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Cevap: 112\frac{11}{2}

Cevap

The correct value of bb is 112\frac{11}{2}.
The correct answer is the value 112\frac{11}{2}. By writing f(x)=mx+bf(x) = mx + b and using the point (2,5)(2, 5), we get m=5b2m = \frac{5-b}{2}. Applying the definition of g(x)=f(x)4g(x) = f(x) - 4 gives g(x)=mx+b4g(x) = mx + b - 4. Since the graph of gg has an xx-intercept of (6,0)(6, 0), substituting x=6x = 6 and g(6)=0g(6) = 0 gives 6m+b4=06m + b - 4 = 0. Substituting the expression for mm yields 3(5b)+b4=03(5-b) + b - 4 = 0, which simplifies to 112b=011 - 2b = 0, and thus b=112b = \frac{11}{2}.

Adım Adım Çözüm

1
Write the linear function f(x)f(x) in slope-intercept form using the given yy-intercept (0,b)(0, b).
f(x)=mx+bf(x) = mx + b, where mm is the slope of the line.
This sets up the general equation of the line with unknown parameters mm and bb.
2
Substitute the coordinates of the point (2,5)(2, 5) into the equation for f(x)f(x) to express mm in terms of bb.
5=2m+b5 = 2m + b, which simplifies to m=5b2m = \frac{5 - b}{2}.
Since the point lies on the graph of ff, its coordinates must satisfy the equation.
3
Define g(x)g(x) using the relationship g(x)=f(x)4g(x) = f(x) - 4 and apply the xx-intercept (6,0)(6, 0).
g(x)=mx+b4g(x) = mx + b - 4. Since the xx-intercept is (6,0)(6, 0), we have g(6)=0g(6) = 0, which gives 6m+b4=06m + b - 4 = 0.
The xx-intercept is the point where the output of the function is zero.
4
Substitute the expression for mm from Step 2 into the equation from Step 3 and solve for bb.
6(5b2)+b4=03(5b)+b4=0153b+b4=0112b=0b=1126\left(\frac{5-b}{2}\right) + b - 4 = 0 \Rightarrow 3(5-b) + b - 4 = 0 \Rightarrow 15 - 3b + b - 4 = 0 \Rightarrow 11 - 2b = 0 \Rightarrow b = \frac{11}{2}.
This solves the system of equations to determine the value of the constant bb.

Anahtar Kavram

Linear Functions and Graphs
Soru 1202Soru

Which punctuation mark correctly completes the passage by joining the independent clause to the explanatory details that follow?

Aşağıdaki boşlukları doldurun

In 1992, astronomers Aleksander Wolszczan and Dale Frail announced a discovery that challenged long-held assumptions about the cosmos three terrestrial planets, later named Poltergeist, Phobetor, and Draugr, orbiting a rapidly spinning neutron star. Prior to this finding, scientists believed that the violent supernova explosions marking the death of massive stars would inevitably destroy any orbiting bodies. The detection of these pulsar planets proved that planetary systems could survive, or even form in the aftermath of, such cataclysmic stellar events.
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Cevap

A colon (:) or a dash (—) is correct because it links an independent clause to a list or explanatory detail at the end of a sentence.
The correct punctuation is a colon (:) or a dash (—). The text preceding the blank is an independent clause, and the text following it is a noun phrase that provides explanatory details about the 'discovery'. Standard English conventions dictate that a colon or a single dash can be used to set off explanatory lists or details following an independent clause. A colon or dash is particularly necessary here because the explanatory phrase contains internal commas, meaning a comma would result in punctuation confusion.

Adım Adım Çözüm

1
Analyze the grammatical structure of the clause preceding the blank.
The clause 'In 1992, astronomers Aleksander Wolszczan and Dale Frail announced a discovery that challenged long-held assumptions about the cosmos' is independent and can stand alone as a complete sentence.
This establishes that the preceding clause can be followed by a colon or dash.
2
Analyze the structure of the phrase following the blank.
The phrase 'three terrestrial planets, later named Poltergeist, Phobetor, and Draugr, orbiting a rapidly spinning neutron star' is a noun phrase functioning as an appositive or explanatory detail, not an independent clause.
Since it is not an independent clause, a semicolon cannot be used to join them.
3
Select the correct punctuation mark based on punctuation rules.
A colon or a dash is appropriate here because both can connect an independent clause to an explanatory phrase or list. A comma is incorrect because the following phrase contains internal commas ('later named Poltergeist, Phobetor, and Draugr'), so adding another comma would create structural confusion.
This confirms that a colon (:) or a dash (—) is the only grammatically sound choice.

Anahtar Kavram

Colons and dashes can join an independent clause to explanatory details, lists, or appositives at the end of a sentence, especially when those details contain internal punctuation.
Soru 1203Soru

The passage below contains a blank. Which punctuation mark correctly sets off the nonessential element in the sentence?

Aşağıdaki boşlukları doldurun

In 1953, botanist Katherine Esau published her landmark book *Plant Anatomy*, which remains a definitive text on plant biology. Prior to Esau's work, the field focused primarily on static descriptions of plant tissues. Esau, who was awarded the National Medal of Science in 1989 revolutionized the study of plant anatomy by integrating microscopic structural details with dynamic developmental processes.
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Cevap

comma (or ,)
The correct answer is a comma. The relative clause 'who was awarded the National Medal of Science in 1989' is nonessential and must be separated from the rest of the sentence. Since a comma is used immediately after 'Esau' to introduce the clause, a matching comma must be placed after '1989' to close the clause before the main verb 'revolutionized'.

Adım Adım Çözüm

1
Identify the nonessential clause in the sentence.
The phrase 'who was awarded the National Medal of Science in 1989' is a nonessential relative clause modifying the proper noun 'Esau'.
This clause provides descriptive information that is not essential to identifying the subject or understanding the core meaning of the main clause.
2
Identify the punctuation mark used to introduce the clause.
A comma is placed immediately after 'Esau' to open the clause.
Nonessential elements must be set off with matching pairs of punctuation to maintain grammatical symmetry.
3
Select the matching punctuation mark to close the clause.
A comma is required in the blank after '1989' to close the clause before the verb 'revolutionized'.
Using any other punctuation mark (like a dash or parenthesis) or omitting the punctuation entirely would result in asymmetrical punctuation, which is incorrect in Standard English.

Anahtar Kavram

Punctuation of Nonessential Elements
Soru 1204Soru

Which expression is equivalent to 3(2x5)(x4)3(2x - 5) - (x - 4)?

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Cevap: 5x115x - 11

Cevap

5x115x - 11
To find the equivalent expression, apply the distributive property to both parts of the expression: 3(2x5)3(2x - 5) expands to 6x156x - 15, and (x4)-(x - 4) expands to x+4-x + 4. Combining the variable terms gives 6xx=5x6x - x = 5x. Combining the constant terms gives 15+4=11-15 + 4 = -11. Thus, the simplified equivalent expression is 5x115x - 11.

Adım Adım Çözüm

1
Distribute the number 33 to each term inside the first set of parentheses.
3(2x5)=6x153(2x - 5) = 6x - 15
To eliminate the first set of parentheses by applying the distributive property.
2
Distribute the negative sign (equivalent to multiplying by 1-1) to each term inside the second set of parentheses.
(x4)=x+4-(x - 4) = -x + 4
To eliminate the second set of parentheses, ensuring the negative sign is applied to both xx and 4-4.
3
Combine the like terms (the variable terms and the constant terms).
(6xx)+(15+4)=5x11(6x - x) + (-15 + 4) = 5x - 11
To simplify the expression into its final equivalent form.

Anahtar Kavram

Equivalent Algebraic Expressions
Soru 1205Soru

The table below shows some values of the linear function hh.

xxh(x)h(x)
22k4k - 4
55k+8k + 8
882k+22k + 2

If kk is a constant, what is the value of kk?

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Cevap: 18

Cevap

The value of the constant kk is 1818.
Since the function hh is linear, its rate of change (slope) is constant. Calculating the slope using the first two coordinate pairs (2,k4)(2, k - 4) and (5,k+8)(5, k + 8) gives (k+8)(k4)52=123=4\frac{(k + 8) - (k - 4)}{5 - 2} = \frac{12}{3} = 4. Using the next two coordinate pairs (5,k+8)(5, k + 8) and (8,2k+2)(8, 2k + 2) gives the slope as (2k+2)(k+8)85=k63\frac{(2k + 2) - (k + 8)}{8 - 5} = \frac{k - 6}{3}. Setting these two slope values equal to each other gives the equation k63=4\frac{k - 6}{3} = 4. Multiplying both sides by 33 results in k6=12k - 6 = 12, and adding 66 to both sides yields k=18k = 18.

Adım Adım Çözüm

1
Identify that the rate of change (slope) of a linear function is constant between any two points.
The slope calculated from the first two points must equal the slope calculated from the second and third points.
This relationship allows us to set up an algebraic equation to solve for the unknown constant kk.
2
Calculate the slope using the first two points: (2,k4)(2, k - 4) and (5,k+8)(5, k + 8).
Slope = (k+8)(k4)52=k+8k+43=123=4\frac{(k + 8) - (k - 4)}{5 - 2} = \frac{k + 8 - k + 4}{3} = \frac{12}{3} = 4.
This simplifies to a constant numerical value of 44 for the slope of the function.
3
Calculate the slope using the second and third points: (5,k+8)(5, k + 8) and (8,2k+2)(8, 2k + 2).
Slope = (2k+2)(k+8)85=2k+2k83=k63\frac{(2k + 2) - (k + 8)}{8 - 5} = \frac{2k + 2 - k - 8}{3} = \frac{k - 6}{3}.
This provides a second expression for the slope in terms of the variable kk.
4
Equate the two slope expressions and solve for kk.
k63=4    k6=12    k=18\frac{k - 6}{3} = 4 \implies k - 6 = 12 \implies k = 18.
Setting the two expressions equal and solving isolating kk gives the correct value of 1818.

Anahtar Kavram

A linear function has a constant rate of change (slope) between any two points on its graph.
Soru 1206Soru

A local delivery service charges a flat fee of 1212 dollars plus 1.501.50 dollars per mile to deliver a package. If a customer wants to spend no more than 3030 dollars for a package delivery, what is the maximum number of miles the delivery service can travel?

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Cevap: 12

Cevap

The maximum number of miles the delivery service can travel is 12.
The total delivery cost is the sum of the flat fee (1212 dollars) and the rate per mile (1.501.50 dollars multiplied by mm miles), which is represented by 1.50m+121.50m + 12. Since the total cost cannot exceed 3030 dollars, the inequality is 1.50m+12301.50m + 12 \leq 30. Subtracting 1212 from both sides gives 1.50m181.50m \leq 18. Dividing both sides by 1.501.50 yields m12m \leq 12. Thus, the maximum distance the delivery service can travel is 1212 miles.

Adım Adım Çözüm

1
Set up the inequality representing the delivery cost constraint.
1.50m+12301.50m + 12 \leq 30
The total cost of the delivery is the flat fee of 1212 dollars plus 1.501.50 dollars per mile, mm, which must be less than or equal to the budget of 3030 dollars.
2
Subtract 12 from both sides of the inequality.
1.50m181.50m \leq 18
To isolate the variable term, subtract the constant flat fee from both sides of the inequality.
3
Divide both sides of the inequality by 1.50.
m12m \leq 12
Dividing by the per-mile rate calculates the maximum distance constraint on the variable mm.

Anahtar Kavram

Setting up and solving a one-variable linear inequality to determine a maximum boundary value in context.
Soru 1207Soru

The following passage is adapted from an archaeological study of ancient trade networks. Based on the context of the passage, what is the correct form of the noun 'vessel' that should fill the blank?

Aşağıdaki boşlukları doldurun

To construct a precise chronology of the region's ancient trade networks, archaeologists analyzed the chemical composition of several newly excavated clay vessels. By identifying the unique trace elements in the clay, the researchers concluded that the pottery's distinct mineral signature could reliably trace each origin to a single, localized kiln in the river valley.
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Cevap

vessel's
The correct answer is the singular possessive form 'vessel's'. The word is preceded by the singular determiner 'each', which requires a singular noun rather than a plural one. Furthermore, the noun modifies 'origin', meaning it must be in the possessive case to show the relationship between the vessel and its origin.

Adım Adım Çözüm

1
Identify the syntactic role of the word in the blank.
The blank precedes the noun 'origin' and must modify it to indicate relationship or association, which requires a possessive form.
Nouns modifying other nouns to show possession or relationship must be in the possessive case.
2
Determine the number (singular or plural) of the noun based on surrounding modifiers.
The determiner 'each' precedes the blank and specifies a singular noun.
The word 'each' is grammatically singular and must modify a singular noun.
3
Combine the singular number and possessive case to form the correct word.
The singular possessive form of 'vessel' is 'vessel's'.
Singular nouns are made possessive by adding an apostrophe followed by the letter 's'.

Anahtar Kavram

Plural and Possessive Nouns
Soru 1208Soru

In 1418, the builders of the Florence Cathedral faced a seemingly impossible engineering challenge: constructing a massive dome without any temporary wooden scaffolding. The architect Filippo Brunelleschi ______ devised an ingenious solution that utilized a herringbone brick pattern to distribute weight. This self-supporting design allowed the dome to be built without collapsing inward during construction, forever altering the course of Renaissance architecture.

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

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Cevap: , who had studied the ancient construction techniques of the Roman Pantheon,

Cevap

The phrase that begins and ends with a comma: ', who had studied the ancient construction techniques of the Roman Pantheon,'
The relative clause 'who had studied the ancient construction techniques of the Roman Pantheon' provides extra, nonrestrictive information about Filippo Brunelleschi. In Standard Written English, nonessential elements must be set off from the rest of the sentence using matching punctuation marks on both sides. The correct choice employs a pair of commas to appropriately isolate the clause. Other options fail because they create asymmetrical punctuation by mixing different marks or omitting one of the boundary markers.

Adım Adım Çözüm

1
Identify the boundary of the relative clause in the sentence.
The relative clause is 'who had studied the ancient construction techniques of the Roman Pantheon'.
Determining where the clause begins and ends is necessary to apply the punctuation rules.
2
Determine if the relative clause is essential or nonessential to the sentence's meaning.
The relative clause is nonessential (nonrestrictive) because it modifies the specific proper noun 'Filippo Brunelleschi' and its removal does not change the core meaning of the sentence.
Nonessential elements must be set off with punctuation, whereas essential elements are not punctuated.
3
Apply the matching punctuation rule to set off the nonessential relative clause.
The clause must start with a comma and end with a comma (or start and end with em dashes/parentheses) to maintain grammatical symmetry.
Standard English conventions require matching punctuation marks on both sides of a nonessential element.

Anahtar Kavram

Punctuation of Nonessential Elements
Tahmini Süre:1m 0s
Soru 1209Soru

A graphic designer is exporting images for a website. There are two types of images: standard images and high-resolution images. Each standard image, xx, requires 3 megabytes (MB) of storage and takes 2 seconds to upload. Each high-resolution image, yy, requires 8 MB of storage and takes 5 seconds to upload. The designer must limit the total storage of the exported images to at most 120 MB and the total upload time to at least 60 seconds. Which of the following systems of inequalities models this situation?

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Cevap: 3x+8y1203x + 8y \leq 120
2x+5y602x + 5y \geq 60

Cevap

The system of inequalities is 3x+8y1203x + 8y \leq 120 and 2x+5y602x + 5y \geq 60.
The correct system models the limits correctly. The storage constraint is represented by 3x+8y1203x + 8y \leq 120 since 'at most' corresponds to a less-than-or-equal-to sign. The upload time constraint is represented by 2x+5y602x + 5y \geq 60 since 'at least' corresponds to a greater-than-or-equal-to sign.

Adım Adım Çözüm

1
Set up the inequality for the storage constraint.
3x+8y1203x + 8y \leq 120
Each standard image uses 3 megabytes and each high-resolution image uses 8 megabytes. The total storage must be at most (less than or equal to) 120 megabytes.
2
Set up the inequality for the upload time constraint.
2x+5y602x + 5y \geq 60
Each standard image takes 2 seconds and each high-resolution image takes 5 seconds to upload. The total upload time must be at least (greater than or equal to) 60 seconds.
3
Combine both inequalities into a system.
The system containing 3x+8y1203x + 8y \leq 120 and 2x+5y602x + 5y \geq 60.
Both constraints must be satisfied simultaneously.

Anahtar Kavram

Translating verbal constraints into systems of linear inequalities in two variables.
Soru 1210Soru

In the xyxy-plane, a system of two linear equations has no solutions. One of the equations in the system is 4x6y=154x - 6y = 15. The graph of the second equation is a line that passes through the points (3,k)(3, k) and (9,7)(9, 7), where kk is a constant. What is the value of kk?

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Cevap: 3

Cevap

The value of kk is 33.
For a system of linear equations to have no solutions, the lines representing the equations must be parallel, which means they have equal slopes but different y-intercepts. The first equation, 4x6y=154x - 6y = 15, can be rewritten in slope-intercept form as y=23x2.5y = \frac{2}{3}x - 2.5, showing its slope is 23\frac{2}{3}. The slope of the second line, passing through (3,k)(3, k) and (9,7)(9, 7), is given by 7k93=7k6\frac{7 - k}{9 - 3} = \frac{7 - k}{6}. Setting the two slopes equal yields 23=7k6\frac{2}{3} = \frac{7 - k}{6}. Multiplying both sides by 66 gives 4=7k4 = 7 - k, which solves to k=3k = 3. Substituting k=3k = 3 back into the second line gives y=23x+1y = \frac{2}{3}x + 1. Since the slopes are equal and the y-intercepts (2.5-2.5 and 11) are different, the lines are parallel and distinct, confirming there are no solutions.

Adım Adım Çözüm

1
Find the slope of the first line by converting the equation to slope-intercept form.
Slope is 23\frac{2}{3} and y-intercept is 2.5-2.5.
Converting 4x6y=154x - 6y = 15 to y=23x2.5y = \frac{2}{3}x - 2.5 reveals the slope of the first line.
2
Express the slope of the second line using the coordinates of the two points on the line.
Slope expression is 7k6\frac{7 - k}{6}.
Applying the slope formula y2y1x2x1\frac{y_2 - y_1}{x_2 - x_1} to (3,k)(3, k) and (9,7)(9, 7) defines the slope in terms of kk.
3
Equate the two slopes and solve for the unknown parameter.
k=3k = 3
Since the system has no solutions, the lines must be parallel and have equal slopes. Setting 23=7k6\frac{2}{3} = \frac{7 - k}{6} and solving gives k=3k = 3.

Anahtar Kavram

For a system of two linear equations to have no solutions, the lines representing the equations must be parallel, which requires them to have the same slope but different y-intercepts.
Tahmini Süre:2m 0s
Soru 1211Soru

If 3x2(y5)=123x - 2(y - 5) = 12 and x=8x = 8, what is the value of yy?

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Cevap: 11

Cevap

11
The correct answer is 11. Substituting x=8x = 8 into the equation gives 3(8)2(y5)=123(8) - 2(y - 5) = 12, which simplifies to 242y+10=1224 - 2y + 10 = 12. Combining the constants on the left side yields 342y=1234 - 2y = 12. Subtracting 34 from both sides gives 2y=22-2y = -22. Finally, dividing both sides by 2-2 yields y=11y = 11.

Adım Adım Çözüm

1
Substitute x=8x = 8 into the given equation.
3(8)2(y5)=123(8) - 2(y - 5) = 12, which simplifies to 242(y5)=1224 - 2(y - 5) = 12.
This isolates the variable yy by replacing the variable xx with its given value.
2
Distribute 2-2 to the terms inside the parentheses.
242y+10=1224 - 2y + 10 = 12.
Multiplying 2-2 by yy gives 2y-2y, and multiplying 2-2 by 5-5 gives +10+10 because the product of two negative numbers is positive.
3
Combine the constant terms on the left side of the equation and subtract the result from both sides.
342y=122y=2234 - 2y = 12 \Rightarrow -2y = -22.
Combining 2424 and 1010 gives 3434. Subtracting 3434 from both sides isolates the variable term 2y-2y.
4
Divide both sides by 2-2 to solve for yy.
y=11y = 11.
Dividing both sides of the equation by the coefficient of the variable term isolates the variable.

Anahtar Kavram

Solving linear equations in two variables by substitution and isolation.
Tahmini Süre:45s
Soru 1212Soru

Which of the following represents all possible values of xx that satisfy the inequality 2(x5)>6-2(x - 5) > 6?

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Cevap: x<2x < 2

Cevap

The inequality is satisfied when x<2x < 2.
Dividing both sides of the inequality 2(x5)>6-2(x - 5) > 6 by 2-2 yields x5<3x - 5 < -3, where the inequality sign is reversed because of division by a negative number. Adding 55 to both sides of x5<3x - 5 < -3 results in x<2x < 2.

Adım Adım Çözüm

1
Divide both sides of the inequality 2(x5)>6-2(x - 5) > 6 by 2-2.
x5<3x - 5 < -3
Dividing both sides of an inequality by a negative number requires reversing the direction of the inequality sign.
2
Add 55 to both sides of the inequality to isolate xx.
x<2x < 2
To solve for xx, eliminate the constant term 5-5 on the left side of the inequality.

Anahtar Kavram

Solving linear inequalities in one variable, including reversing the inequality sign when multiplying or dividing by a negative number.
Soru 1213Soru
A system of inequalities is shown below.
y3x+15y2x+2\begin{aligned} y &\leq -3x + 15 \\ y &\leq 2x + 2 \end{aligned}
If (x,y)(x, y) is a solution to the system, what is the maximum possible integer value of yy?
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Cevap: 7

Cevap

7
The maximum value of yy in the system occurs at the intersection of the boundary lines y=3x+15y = -3x + 15 and y=2x+2y = 2x + 2. Solving for the intersection gives x=2.6x = 2.6 and y=7.2y = 7.2. Since any point in the solution set must satisfy y7.2y \leq 7.2, the largest possible integer value for yy is 7. We can confirm this is achievable because when y=7y = 7, xx can be any value in the range [2.5,2.67][2.5, 2.67] (such as x=2.6x=2.6), which satisfies both inequalities.

Adım Adım Çözüm

1
Find the intersection point of the boundary lines.
Set the two equations equal to find the xx-coordinate: 3x+15=2x+2    5x=13    x=2.6-3x + 15 = 2x + 2 \implies 5x = 13 \implies x = 2.6.
The maximum value of yy in a system bounded from above by two lines with opposing slopes occurs at their point of intersection.
2
Calculate the corresponding maximum yy-value.
Substitute x=2.6x = 2.6 into either boundary equation: y=2(2.6)+2=7.2y = 2(2.6) + 2 = 7.2.
This determines the absolute upper bound of yy for any coordinate pair in the solution set.
3
Determine the maximum integer value of yy.
Since y7.2y \leq 7.2, the largest integer value that yy can take is 7.
The question asks specifically for the maximum integer value of yy, and since 77.27 \leq 7.2, a solution exists at this yy-value.
4
Verify that a solution exists for y=7y = 7.
For y=7y = 7, the system requires 73x+15    x2.677 \leq -3x + 15 \implies x \leq 2.67 and 72x+2    x2.57 \leq 2x + 2 \implies x \geq 2.5. The interval [2.5,2.67][2.5, 2.67] is non-empty, so valid solutions (e.g., (2.6,7)(2.6, 7)) exist.
This confirms that y=7y = 7 is attainable within the feasible region.

Anahtar Kavram

Optimization of variables within systems of linear inequalities
Soru 1214Soru

A graphic designer allocates their weekly work time between designing layouts, which takes dd hours, and client consultations, which takes cc hours. The designer works a maximum of 35 hours per week. Additionally, the designer spends at least twice as much time designing layouts as they do in client consultations. Which of the following systems of inequalities represents this situation?

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Cevap: d+c35d2c\begin{aligned} d + c &\leq 35 \\ d &\geq 2c \end{aligned}

Cevap

The system with the inequalities d+c35d + c \leq 35 and d2cd \geq 2c
The system containing the inequalities d+c35d + c \leq 35 and d2cd \geq 2c is correct. The constraint 'works a maximum of 35 hours per week' means the sum of the hours, d+cd + c, must be less than or equal to 35 (d+c35d + c \leq 35). The constraint 'spends at least twice as much time designing layouts as they do in client consultations' means that design hours, dd, must be greater than or equal to twice the consultation hours, cc (d2cd \geq 2c).

Adım Adım Çözüm

1
Identify the inequality representing the limit on total weekly hours.
d+c35d + c \leq 35
The phrase 'works a maximum of 35 hours per week' means the total hours spent on designing (dd) and consulting (cc) cannot exceed 35.
2
Identify the inequality representing the relative relationship between designing and consulting hours.
d2cd \geq 2c
The phrase 'at least twice as much time designing layouts as they do in client consultations' means the design hours (dd) must be greater than or equal to two times the consultation hours (2c2c).
3
Combine the individual inequalities into a system.
The system consists of d+c35d + c \leq 35 and d2cd \geq 2c.
Both conditions must be satisfied simultaneously to represent the designer's weekly schedule constraint.

Anahtar Kavram

Systems of Linear Inequalities in Two Variables
Tahmini Süre:1m 0s
Soru 1215Soru

A closed triangular region in the coordinate plane is defined by the following system of linear inequalities:

y2x4yx+8x1\begin{aligned} y &\geq 2x - 4 \\ y &\leq -x + 8 \\ x &\geq 1 \end{aligned}

What is the maximum possible value of the expression 2x+y2x + y for any point (x,y)(x, y) that lies within or on the boundary of this region?

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Cevap: 12

Cevap

The maximum possible value of the expression 2x+y2x + y is 12.
To find the maximum possible value of the expression 2x+y2x + y subject to the given system of inequalities, we first identify the boundary lines and find the vertices of the bounded triangular region in the coordinate plane. The boundary lines are y=2x4y = 2x - 4, y=x+8y = -x + 8, and x=1x = 1. The intersection of y=2x4y = 2x - 4 and y=x+8y = -x + 8 occurs at x=4,y=4x = 4, y = 4, which gives vertex (4,4)(4, 4). The intersection of y=2x4y = 2x - 4 and x=1x = 1 occurs at (1,2)(1, -2). The intersection of y=x+8y = -x + 8 and x=1x = 1 occurs at (1,7)(1, 7). Evaluating the linear expression 2x+y2x + y at these three vertices gives 2(4)+4=122(4) + 4 = 12, 2(1)2=02(1) - 2 = 0, and 2(1)+7=92(1) + 7 = 9. By the corner point theorem, the maximum value of a linear function on a closed polygonal region occurs at one of the vertices. Comparing the values, the maximum possible value is 12.

Adım Adım Çözüm

1
Find the vertex formed by the intersection of the boundary lines y=2x4y = 2x - 4 and y=x+8y = -x + 8.
Vertex A(4,4)A(4, 4)
Setting the two equations equal: 2x4=x+8    3x=12    x=42x - 4 = -x + 8 \implies 3x = 12 \implies x = 4. Substituting x=4x = 4 back into either equation yields y=4y = 4.
2
Find the vertex formed by the intersection of the boundary line y=2x4y = 2x - 4 and the vertical line x=1x = 1.
Vertex B(1,2)B(1, -2)
Substituting x=1x = 1 into y=2x4y = 2x - 4 gives y=2(1)4=2y = 2(1) - 4 = -2.
3
Find the vertex formed by the intersection of the boundary line y=x+8y = -x + 8 and the vertical line x=1x = 1.
Vertex C(1,7)C(1, 7)
Substituting x=1x = 1 into y=x+8y = -x + 8 gives y=1+8=7y = -1 + 8 = 7.
4
Evaluate the expression 2x+y2x + y at each of the three vertices.
At A(4,4)A(4, 4), the value is 1212; at B(1,2)B(1, -2), the value is 00; at C(1,7)C(1, 7), the value is 99.
According to the Corner Point Theorem of linear programming, the maximum or minimum of a linear objective function on a closed bounded region must occur at one of the vertices.
5
Identify the maximum value from the evaluated points.
The maximum value is 12.
Comparing the values 12, 0, and 9 shows that 12 is the largest value.

Anahtar Kavram

Linear Programming and Systems of Inequalities
Soru 1216Soru

An online streaming service offers the two monthly subscription plans described in the table below:

PlanMonthly feeCost per premium movie rental
Plan A$12$1.50
Plan B$27 (includes first 4 rentals)$0.75 (for each rental after the first 4)

If a user rented mm premium movies in a month, where m>4m > 4, and the total cost for both plans would be the same, what is the value of mm?

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Cevap: 16

Cevap

The value of mm that results in the same total monthly cost for both plans is 16.
The correct answer of 16 represents the exact number of premium movie rentals where the total monthly cost for both plans is equal to $36. Any other number of movie rentals will result in different costs for the two plans.

Adım Adım Çözüm

1
Define the cost equation for Plan A
CostA=12+1.50m\text{Cost}_A = 12 + 1.50m
Plan A charges a flat 12monthlyfeeplus12 monthly fee plus 1.50 for each of the mm movies rented.
2
Define the cost equation for Plan B
CostB=27+0.75(m4)\text{Cost}_B = 27 + 0.75(m - 4)
Plan B charges a 27monthlyfeethatcoversthefirst4movies,and27 monthly fee that covers the first 4 movies, and 0.75 for each of the m4m - 4 additional movies rented because m>4m > 4.
3
Equate the two cost expressions and solve for mm
12+1.50m=27+0.75(m4)    12+1.50m=24+0.75m    0.75m=12    m=1612 + 1.50m = 27 + 0.75(m - 4) \implies 12 + 1.50m = 24 + 0.75m \implies 0.75m = 12 \implies m = 16
To find when the costs are identical, set the two algebraic expressions equal to each other and isolate the variable mm.

Anahtar Kavram

Setting up and solving linear equations in one variable from context

Alternatif Yöntem

Instead of setting up full equations, we can look at the cost difference at m=4m = 4. At 44 movies, Plan A costs 12+1.50(4)=1812 + 1.50(4) = 18 dollars, and Plan B costs 2727 dollars (since 44 movies are included). The price difference is 2718=927 - 18 = 9 dollars. For each movie rented beyond 44, the cost of Plan A increases by 1.501.50 dollars while Plan B only increases by 0.750.75 dollars. The rate of change difference is 1.500.75=0.751.50 - 0.75 = 0.75 dollars per movie. To bridge the initial 99 dollar difference, the user needs to rent 90.75=12\frac{9}{0.75} = 12 more movies. Thus, the total number of movies is 4+12=164 + 12 = 16.
Tahmini Süre:1m 30s
Soru 1217Soru

Many desert plants have evolved specialized root systems that are uniquely adapted to survive in extremely arid environments. The saguaro cactus, for instance, grows a shallow network of roots that spreads horizontally from its ______ this extensive structure allows the cactus to absorb water rapidly from even the briefest rainfall events.

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

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Cevap: base;

Cevap

base;
The option ending with a semicolon correctly links two independent clauses without a coordinating conjunction. Since both 'The saguaro cactus... grows a shallow network of roots that spreads horizontally from its base' and 'this extensive structure allows...' can stand alone as complete sentences, a semicolon is appropriate to separate them.

Adım Adım Çözüm

1
Analyze the structure of the two clauses surrounding the blank.
The first clause ('The saguaro cactus... grows a shallow network of roots that spreads horizontally from its base') and the second clause ('this extensive structure allows...') are both independent clauses.
Identifying the clause types is necessary to determine the appropriate punctuation or coordinating conjunction needed to connect them.
2
Determine the logical relationship between the two clauses.
The second clause explains the benefit or function of the structure mentioned in the first clause. The relationship is explanatory, not contrastive.
This helps rule out inappropriate coordinating conjunctions like 'but'.
3
Select the correct punctuation to link the independent clauses.
A semicolon is the standard way to link two independent clauses when no coordinating conjunction is used.
It avoids both a comma splice and a run-on sentence while maintaining grammatical correctness.

Anahtar Kavram

Semicolons are used to connect two closely related independent clauses that are not joined by a coordinating conjunction.
Soru 1218Soru

The table below shows some values for a linear function ff, where kk is a positive constant.

xxf(x)f(x)
0033
kk2k+62k + 6
4k4k2727

What is the slope of the graph of y=f(x)y = f(x) in the xyxy-plane?

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Cevap: 4

Cevap

The slope of the graph of ff is 44.
The correct answer is 44. A linear function can be written in the form f(x)=mx+bf(x) = mx + b, where mm is the slope and bb is the yy-intercept. Since the yy-intercept of the graph of ff is (0,3)(0, 3), we have b=3b = 3, so the function is f(x)=mx+3f(x) = mx + 3. Using the given points, we can set up the equations f(k)=mk+3=2k+6f(k) = mk + 3 = 2k + 6 and f(4k)=4mk+3=27f(4k) = 4mk + 3 = 27. Solving this system yields mk=6mk = 6 and 2k=32k = 3, which gives k=1.5k = 1.5. Substituting k=1.5k = 1.5 into mk=6mk = 6 gives the slope m=4m = 4.

Adım Adım Çözüm

1
Express the linear function f(x)f(x) using the slope-intercept form and the given yy-intercept.
f(x)=mx+3f(x) = mx + 3, where mm is the slope and the yy-intercept is (0,3)(0, 3).
A linear function has the general form f(x)=mx+bf(x) = mx + b. The table indicates that when x=0x = 0, f(x)=3f(x) = 3, which gives the yy-intercept (0,3)(0, 3) and establishes b=3b = 3.
2
Use the point (k,2k+6)(k, 2k + 6) from the table to write an equation involving mm and kk.
mk+3=2k+6    mk=2k+3mk + 3 = 2k + 6 \implies mk = 2k + 3.
Substituting x=kx = k into the function expression gives f(k)=mk+3f(k) = mk + 3. Setting this equal to the table value 2k+62k + 6 allows us to express mkmk in terms of kk.
3
Use the point (4k,27)(4k, 27) from the table to write another equation involving mm and kk, and solve for the product mkmk.
4mk+3=27    4mk=24    mk=64mk + 3 = 27 \implies 4mk = 24 \implies mk = 6.
Substituting x=4kx = 4k into the function expression gives f(4k)=4mk+3f(4k) = 4mk + 3. Setting this equal to the table value 2727 allows us to solve directly for the numerical value of mkmk.
4
Substitute the value of mkmk into the equation from Step 2 to solve for the constant kk.
6=2k+3    2k=3    k=1.56 = 2k + 3 \implies 2k = 3 \implies k = 1.5.
By replacing mkmk with 66 in the equation mk=2k+3mk = 2k + 3, we get a single-variable linear equation that we can solve for kk.
5
Solve for the slope mm using the value of kk and the product mkmk.
m(1.5)=6    m=4m(1.5) = 6 \implies m = 4.
Since mk=6mk = 6 and k=1.5k = 1.5, dividing the product 66 by 1.51.5 yields the slope mm.

Anahtar Kavram

Using coordinate points and intercepts to determine the slope of a linear function represented in a table.
Soru 1219Soru

Research in cognitive psychology has increasingly focused on the phenomenon of cognitive fatigue, which occurs when prolonged mental exertion depletes executive resources. While brief rests can temporarily restore attention, more sustained recovery requires complete detachment from task-related demands ______ individuals who engage in active, non-cognitive leisure activities during breaks show significantly greater cognitive replenishment than those who simply remain idle.

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

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Cevap: ; indeed,

Cevap

The choice with a semicolon followed by the transitional adverb 'indeed' and a comma ('; indeed,').
The passage contains two independent clauses: the first ends with 'demands' and the second begins with 'individuals'. The correct choice uses a semicolon to separate the two independent clauses, followed by the transitional adverb 'indeed' to show that the second clause elaborates on or supports the assertion of the first clause.

Adım Adım Çözüm

1
Analyze the structure of the passage before and after the blank to identify the clause boundaries.
The text before the blank is an independent clause, and the text after the blank is also an independent clause.
Identifying the clause boundaries determines whether we need to link dependent or independent clauses.
2
Determine the appropriate grammatical punctuation and coordinating elements needed to join two independent clauses.
Two independent clauses must be joined by a period, a semicolon, a colon, or a comma coupled with a coordinating conjunction. Linking them with a comma alone creates a comma splice, while linking them with no punctuation creates a run-on sentence.
This narrows down the choices to grammatically correct linking methods.
3
Evaluate the semantic relationship between the two independent clauses to select the correct transition or coordinator.
The second clause reinforces and provides specific evidence for the claim in the first clause. Therefore, an elaborative transitional adverb like 'indeed' is appropriate, whereas a contrastive coordinator like 'but' is logically incorrect.
This ensures that the chosen option is both grammatically correct and semantically logical.

Anahtar Kavram

Clause Boundaries and Linking
Tahmini Süre:1m 0s
Soru 1220Soru
A system of linear equations is given by
kx4y=123x+ky=5\begin{aligned} kx - 4y &= 12 \\ 3x + ky &= 5 \end{aligned}
where kk is a constant. If the system has a unique solution (x,y)(x, y) such that x>0x > 0 and y<0y < 0, how many possible integer values of kk exist?
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Cevap: 9

Cevap

9
To find the number of integer values of kk for which the system has a solution with x>0x > 0 and y<0y < 0, we first express xx and yy in terms of kk. Eliminating yy by multiplying the first equation by kk and the second by 44 and adding them yields (k2+12)x=12k+20(k^2 + 12)x = 12k + 20, or x=12k+20k2+12x = \frac{12k+20}{k^2+12}. Similarly, eliminating xx yields y=5k36k2+12y = \frac{5k-36}{k^2+12}. Since the denominator k2+12k^2 + 12 is strictly positive for all real kk, the sign of xx and yy depends solely on their numerators. For x>0x > 0, we require 12k+20>012k + 20 > 0, which gives k>531.67k > -\frac{5}{3} \approx -1.67. For y<0y < 0, we require 5k36<05k - 36 < 0, which gives k<365=7.2k < \frac{36}{5} = 7.2. Combining these constraints gives the interval 53<k<365-\frac{5}{3} < k < \frac{36}{5}. The integers in this interval are 1,0,1,2,3,4,5,6,-1, 0, 1, 2, 3, 4, 5, 6, and 77, which is a total of 9 integers.

Adım Adım Çözüm

1
Solve the system of equations for xx in terms of kk by eliminating yy.
x=12k+20k2+12x = \frac{12k + 20}{k^2 + 12}
Multiply the first equation by kk and the second by 4, then add them: k(kx4y)+4(3x+ky)=12k+20    (k2+12)x=12k+20k(kx - 4y) + 4(3x + ky) = 12k + 20 \implies (k^2 + 12)x = 12k + 20.
2
Solve the system of equations for yy in terms of kk by eliminating xx.
y=5k36k2+12y = \frac{5k - 36}{k^2 + 12}
Multiply the first equation by 3 and the second by kk, then subtract the first from the second: k(3x+ky)3(kx4y)=5k36    (k2+12)y=5k36k(3x + ky) - 3(kx - 4y) = 5k - 36 \implies (k^2 + 12)y = 5k - 36.
3
Apply the condition x>0x > 0 to find a constraint on kk.
k>53k > -\frac{5}{3}
Since the denominator k2+12k^2 + 12 is positive for all real values of kk, the expression for xx is positive if and only if its numerator is positive: 12k+20>0    k>2012=5312k + 20 > 0 \implies k > -\frac{20}{12} = -\frac{5}{3}.
4
Apply the condition y<0y < 0 to find another constraint on kk.
k<365k < \frac{36}{5}
Similarly, since k2+12>0k^2 + 12 > 0, the expression for yy is negative if and only if its numerator is negative: 5k36<0    k<3655k - 36 < 0 \implies k < \frac{36}{5}.
5
Combine the constraints and count the number of integer values of kk in the resulting interval.
9 integer values
The combined inequality is 53<k<365-\frac{5}{3} < k < \frac{36}{5}, which simplifies to approximately 1.67<k<7.2-1.67 < k < 7.2. The integers in this range are 1,0,1,2,3,4,5,6,7-1, 0, 1, 2, 3, 4, 5, 6, 7, giving a total of 9 integers.

Anahtar Kavram

Solving systems of linear equations with parameters under inequality constraints
ÖncekiSayfa 61 / 140Sonraki
Tüm alıştırma soruları — SAT | Examkin