Tüm alıştırma soruları

2789 soru

Soru 1301Soru

In a study of the migratory monarch butterfly (*Danaus plexippus*), entomologist Dr. Sarah Carter determined that navigating thousands of miles requires not only sensing the Earth's magnetic field but also utilizing the position of the Sun. According to Carter, the butterflies integrate these cues to maintain a consistent heading, ensuring they can locate their overwintering sites, survive harsh weather conditions, and _______

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

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Cevap: establish new colonies in the spring

Cevap

establish new colonies in the spring
The correct choice uses the base verb form 'establish' to match the base verbs 'locate' and 'survive'. The auxiliary verb 'can' governs all three items in the list: they can 'locate', 'survive', and 'establish'. Using any other verb form disrupts this parallel structure.

Adım Adım Çözüm

1
Identify the list of items in the sentence that must be parallel.
The list follows the phrase 'ensuring they can' and includes 'locate their overwintering sites' and 'survive harsh weather conditions'.
Recognizing the structure of the list is essential to determining the grammatical form needed for the final item.
2
Analyze the grammatical structure of the existing list items.
'locate' and 'survive' are both base form verbs that follow the modal auxiliary verb 'can'.
To maintain parallel structure, the final item in the list must also begin with a base form verb.
3
Evaluate the choices to find the one that matches the base verb structure.
The phrase starting with 'establish' is the only option that uses the base form of the verb, completing the parallel sequence: 'locate...', 'survive...', and 'establish...'.
This maintains the grammatical consistency required by the conventions of Standard English.

Anahtar Kavram

Parallel Structure
Tahmini Süre:1m 0s
Soru 1302Öğrencilerin %0'i bunu doğru yanıtladıSoru

In the system of linear equations below, cc is a constant.

2x+3y=12cxy=6\begin{aligned} 2x + 3y &= 12 \\ cx - y &= 6 \end{aligned}

If the system has a unique solution (x,y)(x, y) such that x>0x > 0 and y<0y < 0, which of the following could be the value of cc?

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Cevap: 12\frac{1}{2}

Cevap

The option containing the value 12\frac{1}{2} is correct.
The correct answer is the option containing the value 12\frac{1}{2}. Solving the system of linear equations in terms of the constant cc gives x=302+3cx = \frac{30}{2+3c} and y=12c122+3cy = \frac{12c-12}{2+3c}. For the solution (x,y)(x, y) to lie in the fourth quadrant, we require x>0x > 0 and y<0y < 0. The condition x>0x > 0 is satisfied when 2+3c>02+3c > 0, which simplifies to c>23c > -\frac{2}{3}. Using this result, the condition y<0y < 0 requires the numerator of yy to be negative, so 12c12<012c - 12 < 0, which simplifies to c<1c < 1. Combining these inequalities yields the interval 23<c<1-\frac{2}{3} < c < 1. The only value among the given options that falls within this interval is 12\frac{1}{2}.

Adım Adım Çözüm

1
Express yy in terms of xx and the constant cc using the second equation.
y=cx6y = cx - 6
This allows for substitution into the first equation to solve for xx.
2
Substitute the expression for yy into the first equation and solve for xx.
2x+3(cx6)=12    (2+3c)x18=12    (2+3c)x=30    x=302+3c2x + 3(cx - 6) = 12 \implies (2 + 3c)x - 18 = 12 \implies (2 + 3c)x = 30 \implies x = \frac{30}{2 + 3c}
This isolates the variable xx in terms of the constant cc.
3
Substitute the expression for xx back into the equation for yy to express yy in terms of cc.
y=c(302+3c)6=30c6(2+3c)2+3c=12c122+3cy = c\left(\frac{30}{2 + 3c}\right) - 6 = \frac{30c - 6(2 + 3c)}{2 + 3c} = \frac{12c - 12}{2 + 3c}
This isolates the variable yy in terms of the constant cc.
4
Apply the condition x>0x > 0 to find the constraint on cc.
Since x=302+3c>0x = \frac{30}{2 + 3c} > 0 and the numerator is positive, the denominator must also be positive: 2+3c>0    c>232 + 3c > 0 \implies c > -\frac{2}{3}.
This determines the lower bound for the constant cc.
5
Apply the condition y<0y < 0 to find the constraint on cc.
Since y=12c122+3c<0y = \frac{12c - 12}{2 + 3c} < 0 and the denominator 2+3c2 + 3c is positive, the numerator must be negative: 12c12<0    c<112c - 12 < 0 \implies c < 1.
This determines the upper bound for the constant cc.
6
Combine the inequalities to find the complete range for cc and identify the matching option.
23<c<1-\frac{2}{3} < c < 1. The only value among the options that lies in this interval is 12\frac{1}{2}.
This identifies the correct option based on the mathematical constraints.

Anahtar Kavram

Solving systems of linear equations with parameters and applying quadrant boundary constraints.
Soru 1303Soru

Consider the system of inequalities shown below:

y2x+1y<x+6\begin{aligned} y &\geq 2x + 1 \\ y &< -x + 6 \end{aligned}

Which coordinate pair (x,y)(x, y) is a solution to the system?

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Cevap: (1,4)(1, 4)

Cevap

The coordinate pair (1,4)(1, 4) is a solution to the system of inequalities.
The coordinate pair (1,4)(1, 4) is the correct answer because substituting x=1x = 1 and y=4y = 4 into both inequalities yields true statements: 42(1)+1434 \geq 2(1) + 1 \Rightarrow 4 \geq 3 is true, and 4<1+64<54 < -1 + 6 \Rightarrow 4 < 5 is true.

Adım Adım Çözüm

1
Substitute the coordinates of the correct pair, (1,4)(1, 4), into the first inequality, y2x+1y \geq 2x + 1.
42(1)+1434 \geq 2(1) + 1 \Rightarrow 4 \geq 3, which is true.
To be a solution to the system, the point must satisfy the first inequality.
2
Substitute the same coordinates, (1,4)(1, 4), into the second inequality, y<x+6y < -x + 6.
4<1+64<54 < -1 + 6 \Rightarrow 4 < 5, which is true.
The point must also satisfy the second inequality to be a solution to the entire system.
3
Conclude that since (1,4)(1, 4) satisfies both inequalities, it is a solution to the system.
The point (1,4)(1, 4) is in the solution set.
A coordinate pair is a solution to a system of inequalities if and only if it satisfies every inequality in the system.

Anahtar Kavram

Testing coordinate pairs in a system of linear inequalities by substitution.
Tahmini Süre:45s
Soru 1304Soru

Although the newly formed committee of environmental advocates has proposed several ambitious initiatives to reduce urban carbon emissions, _______ must still secure the substantial funding required for implementation. The group's primary goal is to install energy-efficient solar panels on municipal buildings throughout the city, but without additional financial backing from local businesses, these plans cannot move forward.

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

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Cevap: it

Cevap

The correct pronoun is 'it' because it agrees in number with the singular collective noun 'committee.'
The pronoun 'it' is correct because the antecedent is the singular collective noun 'committee.' Since the committee acts as a single unit in proposing and securing funding, it requires a singular pronoun. Additionally, because the pronoun functions as the subject of the verb phrase 'must still secure,' the subject pronoun 'it' is the correct case.

Adım Adım Çözüm

1
Identify the antecedent of the pronoun to be placed in the blank.
The antecedent is the collective noun 'committee.'
Determining the correct antecedent is necessary to establish pronoun-antecedent agreement.
2
Determine the grammatical number (singular or plural) of the antecedent.
The noun 'committee' is a singular collective noun that functions as a single unit here, as confirmed by the singular verb 'has proposed' in the preceding clause.
The pronoun must agree in number with the antecedent, ignoring the intervening plural noun 'advocates' in the prepositional phrase 'of environmental advocates.'
3
Identify the grammatical case required by the pronoun's function in the clause.
The pronoun functions as the subject of the verb phrase 'must still secure,' meaning a subject-case pronoun is required.
Choosing the correct pronoun requires matching both number and case constraints.
4
Select the option that is singular and in the subject case.
The pronoun 'it' meets these criteria.
The pronoun 'it' is singular and fits the subject position of the clause.

Anahtar Kavram

Pronoun-Antecedent Agreement in Number
Tahmini Süre:45s
Soru 1305Soru

In sociology, the concept of the "third place" refers to social surroundings that exist independently of the two primary environments of home and work. These informal gathering spaces—such as cafes, parks, and libraries—offer individuals opportunities to connect with their local communities. While some urban planners have overlooked their social utility, research suggests that they are vital to civic [blank] they cultivate a sense of shared identity and support public dialogue.

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

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Cevap: life; they

Cevap

life; they
The text contains two independent clauses: "research suggests that they are vital to civic life" and "they cultivate a sense of shared identity and support public dialogue." A semicolon is a grammatically correct way to link two independent clauses without a coordinating conjunction, making "life; they" the correct choice.

Adım Adım Çözüm

1
Analyze the sentence structure before and after the blank.
The clause before the blank ("research suggests that they are vital to civic life") is independent, and the clause after the blank ("they cultivate a sense of shared identity and support public dialogue") is also independent.
Identifying clause types is necessary to determine how they can be grammatically linked.
2
Evaluate the punctuation and conjunctions needed to link two independent clauses.
Two independent clauses can be joined by a semicolon, a period, or a comma followed by a coordinating conjunction.
This helps rule out options that create run-on sentences or comma splices.
3
Check the logical relationship between the two clauses to verify conjunction usage.
The second clause explains why the gathering spaces are vital to civic life, so a contrasting coordinator like "but" is inappropriate.
This ensures the correct transition or punctuation is selected based on context.

Anahtar Kavram

Clause Boundaries and Linking
Tahmini Süre:45s
Soru 1306Soru

To reconstruct past climate patterns, glaciologists Dr. Clara Vance and Dr. Liam Chen analyzed ice cores retrieved from high-altitude glaciers in the Andes. The _______ findings, which detailed a rapid increase in local temperatures during the mid-Holocene, provided crucial evidence that challenged existing models of prehistoric climate stability and prompted a reevaluation of tropical glacier sensitivity.

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

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Cevap: glaciologists'

Cevap

glaciologists'
The correct answer is the plural possessive form 'glaciologists''. The sentence establishes that there are two scientists, Dr. Clara Vance and Dr. Liam Chen, making the noun plural. Because these scientists own or produced the 'findings' mentioned directly after the blank, the noun must also be possessive. For a plural noun ending in -s, possessive case is indicated by placing an apostrophe at the very end of the word.

Adım Adım Çözüm

1
Analyze the context to determine the noun's number (singular or plural).
The text identifies two specific individuals: Dr. Clara Vance and Dr. Liam Chen. Therefore, the noun referring to them ('glaciologists') must be plural.
Identifying the number prevents choosing a singular noun form.
2
Analyze the syntax to determine the noun's case (possessive or non-possessive).
The blank modifies the noun 'findings,' indicating that the findings belong to the scientists. Therefore, the noun must be possessive.
Identifying the case prevents choosing a non-possessive noun form.
3
Combine number and case to select the correct punctuation.
A plural possessive noun that ends in -s is formed by adding an apostrophe after the -s (glaciologists').
This complies with the conventions of Standard English.

Anahtar Kavram

Plural and Possessive Nouns
Tahmini Süre:1m 0s
Soru 1307Soru

A nutritionist is designing a diet plan using two food types, Food A and Food B. The table below shows the amount of protein and carbohydrates, in grams, per gram of each food type:

Food TypeProtein (g)Carbohydrates (g)
Food A0.120.120.080.08
Food B0.180.180.050.05

The nutritionist wants to combine the two foods to obtain a mixture that has a total mass of 250250 grams and contains exactly 3636 grams of protein. How many grams of carbohydrates will be in this mixture?

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Cevap: 17

Cevap

The total amount of carbohydrates in the mixture is 17 grams.
To find the total amount of carbohydrates in the mixture, we first define xx as the mass in grams of Food A and yy as the mass in grams of Food B. Since the total mass of the mixture is 250250 grams, we write the equation x+y=250x + y = 250. Since the total protein in the mixture must be 3636 grams, and Food A and Food B contain 0.120.12 grams and 0.180.18 grams of protein per gram respectively, we write the equation 0.12x+0.18y=360.12x + 0.18y = 36. Multiplying the first equation by 1212 yields 12x+12y=300012x + 12y = 3000, and multiplying the second equation by 100100 yields 12x+18y=360012x + 18y = 3600. Subtracting the first new equation from the second gives 6y=6006y = 600, which simplifies to y=100y = 100. Substituting this back into the first equation gives x+100=250x + 100 = 250, so x=150x = 150. Using these values, the total amount of carbohydrates is 0.08(150)+0.05(100)=12+5=170.08(150) + 0.05(100) = 12 + 5 = 17 grams.

Adım Adım Çözüm

1
Define variables for the mass of each food type.
Let xx be the mass, in grams, of Food A, and let yy be the mass, in grams, of Food B.
To represent the unknown quantities in the system of equations.
2
Set up the system of linear equations.
x+y=250x + y = 250 (total mass equation) and 0.12x+0.18y=360.12x + 0.18y = 36 (total protein equation).
The mixture has a total mass of 250250 grams and must contain exactly 3636 grams of protein.
3
Solve the system of equations for xx and yy.
Multiply the first equation by 1212 to get 12x+12y=300012x + 12y = 3000. Multiply the second equation by 100100 to get 12x+18y=360012x + 18y = 3600. Subtract the first modified equation from the second to get 6y=6006y = 600, which gives y=100y = 100. Substitute y=100y = 100 back into x+y=250x + y = 250 to get x=150x = 150.
To find the specific masses of Food A and Food B required for the mixture.
4
Calculate the total mass of carbohydrates in the mixture.
Total carbohydrates =0.08x+0.05y=0.08(150)+0.05(100)=12+5=17= 0.08x + 0.05y = 0.08(150) + 0.05(100) = 12 + 5 = 17 grams.
The question asks for the total grams of carbohydrates in the final mixture.

Anahtar Kavram

Systems of Linear Equations
Soru 1308Soru

An empty water tank is being filled by two hoses. Hose A fills the tank at a constant rate of 12 gallons per minute. Hose B fills the tank at a constant rate of 15 gallons per minute. Hose A is turned on first, and 5 minutes later, Hose B is also turned on. If both hoses run until the tank contains a total of 330 gallons of water, for how many minutes was Hose A running?

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Cevap: 15

Cevap

15
Let mm be the number of minutes Hose A was running. Since Hose B was turned on 5 minutes after Hose A, Hose B was running for m5m - 5 minutes. The volume of water contributed by Hose A is 12m12m gallons, and the volume of water contributed by Hose B is 15(m5)15(m - 5) gallons. The sum of these volumes is 330 gallons, which gives the equation 12m+15(m5)=33012m + 15(m - 5) = 330. Distributing 15 gives 12m+15m75=33012m + 15m - 75 = 330. Combining like terms yields 27m75=33027m - 75 = 330. Adding 75 to both sides gives 27m=40527m = 405. Dividing both sides by 27 yields m=15m = 15. Thus, Hose A was running for 15 minutes.

Adım Adım Çözüm

1
Define variables for the running time of each hose.
Let Hose A run for mm minutes. Then Hose B runs for m5m - 5 minutes.
Hose B started 5 minutes after Hose A, so it ran for 5 fewer minutes.
2
Set up a linear equation for the total gallons of water.
12m+15(m5)=33012m + 15(m - 5) = 330
The sum of the water from both hoses must equal 330 gallons.
3
Simplify and solve the linear equation.
27m=40527m = 405, which gives m=15m = 15.
Distribute, combine like terms, and isolate the variable mm.

Anahtar Kavram

Setting up and solving a multi-step linear equation in one variable from a real-world context.
Soru 1309Soru

A public library is purchasing new books for its collection. The library plans to buy paperback books for 6eachandhardcoverbooksfor6 each and hardcover books for 20 each. The library has a budget of at most $1,200 for this purchase, wants to buy at most 120 total books, and must purchase at least 45 hardcover books. What is the maximum number of paperback books the library can purchase?

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Cevap: 50

Cevap

The maximum number of paperback books the library can purchase is 50.
The correct maximum number of paperback books is 50. By expressing the budget constraint as p200103hp \le 200 - \frac{10}{3}h, we see that the number of paperback books is maximized when the number of hardcover books, hh, is minimized. Since the library must buy at least 45 hardcover books, we substitute h=45h = 45 into the inequality to get p50p \le 50. This combination also satisfies the total book constraint because 50+45=9550 + 45 = 95, which is less than or equal to 120.

Adım Adım Çözüm

1
Set up the system of inequalities representing the library's constraints.
Let pp be the number of paperbacks and hh be the number of hardcovers. The constraints are 6p+20h12006p + 20h \le 1200, p+h120p + h \le 120, and h45h \ge 45.
This translates the word problem into mathematical inequalities.
2
Isolate the variable pp in the budget inequality to express it in terms of hh.
p200103hp \le 200 - \frac{10}{3}h
This shows how the number of paperbacks depends on the number of hardcovers purchased.
3
Maximize pp by using the minimum possible value of hh.
p200103(45)=50p \le 200 - \frac{10}{3}(45) = 50
To maximize pp, we must minimize hh because buying more hardcovers decreases the remaining budget for paperbacks. The minimum value for hh is 45.
4
Verify if the solution satisfies the remaining total books constraint.
50+45=9512050 + 45 = 95 \le 120, which is true.
This ensures the solution is feasible and does not violate any other constraints.

Anahtar Kavram

Systems of Linear Inequalities in Two Variables
Soru 1310Soru

For a constant kk, the graph of the linear equation kx4y=15kx - 4y = 15 in the xyxy-plane contains the point (3,3)(3, 3). What is the slope of the line?

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Cevap: 2.25

Cevap

2.25
Substituting the coordinates of the point (3,3)(3, 3) into the given equation yields k(3)4(3)=15k(3) - 4(3) = 15, which simplifies to 3k12=153k - 12 = 15. Adding 1212 to both sides gives 3k=273k = 27, and dividing by 33 gives k=9k = 9. Substituting k=9k = 9 back into the original equation gives 9x4y=159x - 4y = 15. To find the slope of the line, the equation can be written in slope-intercept form, y=mx+by = mx + b, by isolating yy. Subtracting 9x9x from both sides gives 4y=9x+15-4y = -9x + 15. Dividing all terms by 4-4 yields y=94x154y = \frac{9}{4}x - \frac{15}{4}, or y=2.25x3.75y = 2.25x - 3.75. Therefore, the slope of the line is 94\frac{9}{4}, or 2.252.25.

Adım Adım Çözüm

1
Substitute the point (3,3)(3, 3) into the equation kx4y=15kx - 4y = 15
3k12=153k - 12 = 15
Since the graph of the equation contains the point (3,3)(3, 3), substituting x=3x = 3 and y=3y = 3 must satisfy the equation.
2
Solve for the constant kk
k=9k = 9
Adding 1212 to both sides of the equation gives 3k=273k = 27. Dividing both sides by 33 yields k=9k = 9.
3
Substitute k=9k = 9 into the equation and rewrite it in slope-intercept form (y=mx+by = mx + b)
y=94x154y = \frac{9}{4}x - \frac{15}{4}
Substituting k=9k = 9 gives 9x4y=159x - 4y = 15. Subtracting 9x9x from both sides gives 4y=9x+15-4y = -9x + 15. Dividing both sides by 4-4 isolates yy.
4
Identify the slope from the slope-intercept form
Slope = 2.252.25 (or 94\frac{9}{4})
In the slope-intercept form y=mx+by = mx + b, the coefficient mm represents the slope of the line.

Anahtar Kavram

Determining the slope of a line from a linear equation by first finding an unknown constant using a given point on the line.
Soru 1311Soru

Which of the following is equivalent to the expression 2x27x4x216x2+4x2x+1\frac{2x^2 - 7x - 4}{x^2 - 16} \cdot \frac{x^2 + 4x}{2x + 1} for all values of xx where the expression is defined?

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Cevap: xx

Cevap

xx
The correct answer is xx because factoring all numerators and denominators of the given product results in (2x+1)(x4)(x4)(x+4)x(x+4)2x+1\frac{(2x + 1)(x - 4)}{(x - 4)(x + 4)} \cdot \frac{x(x + 4)}{2x + 1}. After cancelling the common factors of (2x+1)(2x + 1), (x4)(x - 4), and (x+4)(x + 4), only xx remains.

Adım Adım Çözüm

1
Factor the quadratic expression in the numerator of the first fraction.
2x27x4=(2x+1)(x4)2x^2 - 7x - 4 = (2x + 1)(x - 4)
Finding the factors of the quadratic trinomial allows us to look for common terms to cancel later.
2
Factor the denominator of the first fraction using the difference of squares identity.
x216=(x4)(x+4)x^2 - 16 = (x - 4)(x + 4)
Simplifying the quadratic binomial in the denominator exposes common factors.
3
Factor the numerator of the second fraction by extracting the greatest common factor.
x2+4x=x(x+4)x^2 + 4x = x(x + 4)
Exhibiting the shared variable xx helps identify terms that will cancel with the denominator.
4
Substitute the factored forms back into the original expression and cancel the common factors.
(2x+1)(x4)(x4)(x+4)x(x+4)2x+1=x\frac{(2x + 1)(x - 4)}{(x - 4)(x + 4)} \cdot \frac{x(x + 4)}{2x + 1} = x
The terms (2x+1)(2x + 1), (x4)(x - 4), and (x+4)(x + 4) appear in both the numerator and the denominator, leaving only the factor xx.

Anahtar Kavram

Simplifying rational expressions by factoring and cancelling common factors
Tahmini Süre:1m 30s
Soru 1312Soru

In sociolinguistic studies of bilingualism, researchers analyze how speakers transition between languages within a single conversation. For decades, early academic theories incorrectly characterized this code-switching behavior as a sign of mental fatigue or lexical deficiencies______ contemporary linguists recognize that the practice is actually a highly structured, rule-governed phenomenon requiring advanced cognitive control and linguistic competence.

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

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Cevap: ; however,

Cevap

The semicolon followed by the conjunctive adverb 'however' and a comma
The transition links two independent clauses. A semicolon followed by a conjunctive adverb and a comma is the standard way to connect two independent clauses when expressing a relationship of contrast.

Adım Adım Çözüm

1
Identify the clause boundary and determine the grammatical structure of the clauses on either side of the blank.
The text before the blank is an independent clause ('For decades... deficiencies'), and the text after the blank is also an independent clause ('contemporary... competence').
Identifying the clause types is necessary to choose the correct punctuation and linking words.
2
Analyze the logical relationship between the two independent clauses.
The first clause describes an outdated, negative view of code-switching, while the second clause presents a modern, positive view. This indicates a relationship of contrast.
The correct transition word must match the logical flow of contrast between the ideas.
3
Select the option that correctly links the two independent clauses while expressing the contrasting relationship.
A semicolon followed by the conjunctive adverb 'however' and a comma is the grammatically correct way to join these two independent clauses.
This configuration avoids run-on sentences and comma splices, conforming to Standard English conventions.

Anahtar Kavram

Clause Boundaries and Linking
Tahmini Süre:1m 0s
Soru 1313Soru

Which of the following expressions is equivalent to 3(x22x)2(x25x)3(x^2 - 2x) - 2(x^2 - 5x) for all values of xx?

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Cevap: x2+4xx^2 + 4x

Cevap

x2+4xx^2 + 4x
To simplify the given expression, distribute the coefficients outside the parentheses to each term inside. Distributing 33 to (x22x)(x^2 - 2x) yields 3x26x3x^2 - 6x. Distributing 2-2 to (x25x)(x^2 - 5x) yields 2x2+10x-2x^2 + 10x. Grouping and combining the like terms gives (3x22x2)+(6x+10x)(3x^2 - 2x^2) + (-6x + 10x), which simplifies to x2+4xx^2 + 4x.

Adım Adım Çözüm

1
Distribute the number 33 to the terms in the first set of parentheses.
3(x22x)=3x26x3(x^2 - 2x) = 3x^2 - 6x
To eliminate the parentheses by multiplying each term inside by the outer coefficient.
2
Distribute the number 2-2 to the terms in the second set of parentheses.
2(x25x)=2x2+10x-2(x^2 - 5x) = -2x^2 + 10x
To eliminate the second set of parentheses, remembering that multiplying two negative numbers yields a positive product: 2×5x=10x-2 \times -5x = 10x.
3
Combine like terms by grouping the quadratic terms and the linear terms together.
(3x22x2)+(6x+10x)=x2+4x(3x^2 - 2x^2) + (-6x + 10x) = x^2 + 4x
To simplify the expression by adding or subtracting the coefficients of terms with the same variable power.

Anahtar Kavram

Equivalent Algebraic Expressions
Tahmini Süre:45s
Soru 1314Soru

A beverage company produces a fruit juice blend using apple juice and cranberry juice. Let xx represent the volume, in liters, of apple juice, and let yy represent the volume, in liters, of cranberry juice used in one batch of the blend. The production constraints for each batch are modeled by the system of inequalities below:

x+y100x + y \geq 100
y13xy \geq \frac{1}{3}x
y12x+75y \leq -\frac{1}{2}x + 75

What is the maximum possible volume, in liters, of cranberry juice that can be used in a single batch?

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Cevap: 50

Cevap

50
To find the maximum possible value of yy, we examine the bounds of the feasible region. Rewriting the inequalities in terms of xx gives x100yx \geq 100 - y and x1502yx \leq 150 - 2y. Since xx must satisfy both inequalities simultaneously, the lower bound must be less than or equal to the upper bound, meaning 100y1502y100 - y \leq 150 - 2y. Solving this inequality for yy gives y50y \leq 50. The point (50,50)(50, 50) also satisfies the remaining constraint y13xy \geq \frac{1}{3}x, confirming that 50 is the maximum possible value.

Adım Adım Çözüm

1
Isolate xx in the first inequality: x+y100x + y \geq 100 becomes x100yx \geq 100 - y.
x100yx \geq 100 - y
This establishes a lower bound for the volume of apple juice in terms of the volume of cranberry juice.
2
Isolate xx in the third inequality: y12x+75y \leq -\frac{1}{2}x + 75 can be rewritten by subtracting 75 from both sides to get y7512xy - 75 \leq -\frac{1}{2}x, then multiplying by 2-2 and reversing the inequality sign to get x1502yx \leq 150 - 2y.
x1502yx \leq 150 - 2y
This establishes an upper bound for the volume of apple juice in terms of the volume of cranberry juice.
3
Combine the lower and upper bounds of xx: 100yx1502y100 - y \leq x \leq 150 - 2y. For a valid solution to exist, the lower bound must be less than or equal to the upper bound.
100y1502y100 - y \leq 150 - 2y
This allows us to solve directly for the constraint on the cranberry juice volume yy.
4
Solve the inequality 100y1502y100 - y \leq 150 - 2y by adding 2y2y to both sides and subtracting 100 from both sides.
y50y \leq 50
This determines that the maximum possible value for yy is 50.
5
Substitute y=50y = 50 back into the compound inequality to find xx: 10050x1502(50)    50x50100 - 50 \leq x \leq 150 - 2(50) \implies 50 \leq x \leq 50, which means x=50x = 50. Check if the point (50,50)(50, 50) satisfies the remaining inequality y13xy \geq \frac{1}{3}x: 5013(50)16.6750 \geq \frac{1}{3}(50) \approx 16.67, which is true.
The point (50,50)(50, 50) is a valid solution to the system.
This confirms that 50 is a achievable value within the system of inequalities.

Anahtar Kavram

Finding the boundary limits and optimization points within a system of linear inequalities in two variables.
Soru 1315Soru

A hot air balloon is at an altitude of hh meters. The balloon begins to descend at a constant rate. After 33 minutes, the altitude of the balloon is 540540 meters. After 88 minutes, the altitude of the balloon is 390390 meters. If the altitude of the balloon is modeled by a linear function of time, what was the initial altitude of the balloon, in meters?

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Cevap: 630

Cevap

The initial altitude of the balloon was 630 meters.
To find the initial altitude, we model the balloon's descent as a linear equation of the form h(t)=mt+bh(t) = mt + b, where h(t)h(t) is the altitude at time tt, mm is the constant rate of change, and bb is the initial altitude. Using the given points (3,540)(3, 540) and (8,390)(8, 390), we find the slope m=39054083=30m = \frac{390 - 540}{8 - 3} = -30 meters per minute. Substituting m=30m = -30 and the point (3,540)(3, 540) into h(t)=mt+bh(t) = mt + b gives 540=30(3)+b540 = -30(3) + b. Solving for bb yields b=540+90=630b = 540 + 90 = 630 meters.

Adım Adım Çözüm

1
Identify two data points from the problem context
The coordinate points are (3,540)(3, 540) and (8,390)(8, 390)
To define the linear relationship, we need at least two coordinate points representing (time, altitude)
2
Calculate the slope (mm) of the linear function
m=39054083=1505=30m = \frac{390 - 540}{8 - 3} = \frac{-150}{5} = -30
The rate of change represents the speed at which the balloon descends each minute
3
Solve for the vertical intercept (bb) using the slope-intercept form y=mx+by = mx + b
540=30(3)+b    b=630540 = -30(3) + b \implies b = 630
The initial altitude corresponds to the altitude at time t=0t = 0, which is the vertical intercept of the linear function

Anahtar Kavram

Linear Functions and Graphs
Soru 1316Soru

A system of two equations is shown below.

y=x24y = x^2 - 4
y=x2y = x - 2

Which of the following ordered pairs (x,y)(x, y) is a solution to the system?

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Cevap: (2,0)(2, 0)

Cevap

The ordered pair (2,0)(2, 0) is the correct solution to the system.
The ordered pair (2,0)(2, 0) is the correct solution because substituting these values into both equations in the system results in true statements. For the quadratic equation, 0=2240 = 2^2 - 4 simplifies to 0=00 = 0. For the linear equation, 0=220 = 2 - 2 simplifies to 0=00 = 0.

Adım Adım Çözüm

1
Substitute the xx-value and yy-value from the candidate solution (2,0)(2, 0) into the first equation, y=x24y = x^2 - 4.
0=224    0=44    0=00 = 2^2 - 4 \implies 0 = 4 - 4 \implies 0 = 0, which is a true statement.
An ordered pair must satisfy the first equation to be a candidate solution for the system.
2
Substitute the xx-value and yy-value from the candidate solution (2,0)(2, 0) into the second equation, y=x2y = x - 2.
0=22    0=00 = 2 - 2 \implies 0 = 0, which is also a true statement.
An ordered pair must satisfy all equations in the system simultaneously to be a valid solution.

Anahtar Kavram

Verifying a solution to a nonlinear system of equations by substituting the coordinate values into both equations.
Soru 1317Soru

If the expression 6x3+7x214x+192x+5\frac{6x^3 + 7x^2 - 14x + 19}{2x + 5} is equivalent to ax2+bx+c+k2x+5ax^2 + bx + c + \frac{k}{2x + 5} for all x2.5x \neq -2.5, where aa, bb, cc, and kk are constants, what is the value of ab+c+ka - b + c + k?

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Cevap: 14

Cevap

14
Dividing the numerator 6x3+7x214x+196x^3 + 7x^2 - 14x + 19 by the denominator 2x+52x + 5 using polynomial division yields a quotient of 3x24x+33x^2 - 4x + 3 and a remainder of 44. The equivalent expression is 3x24x+3+42x+53x^2 - 4x + 3 + \frac{4}{2x + 5}. Comparing this with the form ax2+bx+c+k2x+5ax^2 + bx + c + \frac{k}{2x + 5} gives the values a=3a = 3, b=4b = -4, c=3c = 3, and k=4k = 4. Substituting these values into ab+c+ka - b + c + k gives 3(4)+3+4=143 - (-4) + 3 + 4 = 14.

Adım Adım Çözüm

1
Perform the first step of polynomial long division by dividing 6x36x^3 by 2x2x.
Quotient term: 3x23x^2; Remainder: 8x214x+19-8x^2 - 14x + 19
To eliminate the highest-degree term of the numerator.
2
Perform the second step of division by dividing 8x2-8x^2 by 2x2x.
Quotient term: 4x-4x; Remainder: 6x+196x + 19
To find the next term of the quotient.
3
Perform the third step of division by dividing 6x6x by 2x2x.
Quotient term: 33; Remainder: 44
To find the constant term of the quotient and the final remainder.
4
Compare the resulting expression 3x24x+3+42x+53x^2 - 4x + 3 + \frac{4}{2x + 5} with the given form to identify the constants aa, bb, cc, and kk.
a=3a = 3, b=4b = -4, c=3c = 3, k=4k = 4
To map the coefficients of equivalent algebraic expressions.
5
Evaluate the expression ab+c+ka - b + c + k using the identified values.
3(4)+3+4=143 - (-4) + 3 + 4 = 14
To obtain the final numeric value requested.

Anahtar Kavram

Equivalent Algebraic Expressions via Polynomial Long Division
Soru 1318Soru

In the xyxy-plane, the region RR consists of all points (x,y)(x, y) that satisfy the system of inequalities below:

3x4y12y2x7x+2y2\begin{aligned} 3x - 4y &\geq -12 \\ y &\geq 2x - 7 \\ x + 2y &\geq 2 \end{aligned}

If (x,y)(x, y) is a point in region RR, what is the maximum possible value of the expression x2yx - 2y?

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Cevap: 4.4

Cevap

4.4
The maximum value of a linear expression over a closed, bounded polygonal region must occur at one of the vertices of that region. By solving the systems of equations for each pair of boundary lines, the vertices of the triangular region are found to be (8,9)(8, 9), (3.2,0.6)(3.2, -0.6), and (1.6,1.8)(-1.6, 1.8). Evaluating the expression x2yx - 2y at each vertex gives 10-10 at (8,9)(8, 9), 4.44.4 at (3.2,0.6)(3.2, -0.6), and 5.2-5.2 at (1.6,1.8)(-1.6, 1.8). Comparing these values, 4.44.4 is the maximum possible value.

Adım Adım Çözüm

1
Find the intersection points of the boundary equations by solving the three systems of two linear equations.
System 1 (3x4y=123x - 4y = -12 and y=2x7y = 2x - 7) yields (8,9)(8, 9).
System 2 (y=2x7y = 2x - 7 and x+2y=2x + 2y = 2) yields (3.2,0.6)(3.2, -0.6).
System 3 (3x4y=123x - 4y = -12 and x+2y=2x + 2y = 2) yields (1.6,1.8)(-1.6, 1.8).
The boundaries of the region are defined by these lines, so the vertices of the region occur at their intersections.
2
Verify that the region defined by the inequalities is the interior of the triangle formed by these vertices by testing a point inside, such as (2,2)(2, 2).
The point (2,2)(2, 2) satisfies all three inequalities:
3(2)4(2)=2123(2) - 4(2) = -2 \geq -12 (True)
22(2)7=32 \geq 2(2) - 7 = -3 (True)
2+2(2)=622 + 2(2) = 6 \geq 2 (True)
This confirms that the region is bounded and the vertices are the extreme points of the closed triangular region.
3
Evaluate the expression x2yx - 2y at each of the three vertices.
At (8,9)(8, 9): 82(9)=108 - 2(9) = -10
At (3.2,0.6)(3.2, -0.6): 3.22(0.6)=3.2+1.2=4.43.2 - 2(-0.6) = 3.2 + 1.2 = 4.4
At (1.6,1.8)(-1.6, 1.8): 1.62(1.8)=1.63.6=5.2-1.6 - 2(1.8) = -1.6 - 3.6 = -5.2
A linear expression defined over a closed, bounded polygonal region reaches its maximum and minimum values at the vertices of that region.
4
Compare the evaluated values to identify the maximum value.
The maximum value is 4.44.4.
Among the three candidate values (10-10, 4.44.4, and 5.2-5.2), 4.44.4 is the greatest.

Anahtar Kavram

Linear programming vertex method for systems of linear inequalities.
Tahmini Süre:3m 0s
Soru 1319Soru

For all positive values of xx, which of the following expressions is equivalent to (8x6)13(8x^6)^{\frac{1}{3}}?

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Cevap: 2x22x^2

Cevap

The expression 2x22x^2
To find an equivalent expression, apply the exponent of 13\frac{1}{3} to each factor inside the parentheses. The expression (8x6)13(8x^6)^{\frac{1}{3}} becomes 813(x6)138^{\frac{1}{3}} \cdot (x^6)^{\frac{1}{3}}. Since 813=83=28^{\frac{1}{3}} = \sqrt[3]{8} = 2, and (x6)13=x613=x2(x^6)^{\frac{1}{3}} = x^{6 \cdot \frac{1}{3}} = x^2, the simplified expression is 2x22x^2.

Adım Adım Çözüm

1
Apply the power of a product rule, (ab)n=anbn(ab)^n = a^n b^n, to distribute the exponent of 13\frac{1}{3} to both the coefficient and the variable term.
(8x6)13=813(x6)13(8x^6)^{\frac{1}{3}} = 8^{\frac{1}{3}} \cdot (x^6)^{\frac{1}{3}}
This separates the numerical coefficient and the variable part to simplify them individually.
2
Simplify the numerical coefficient by evaluating the cube root of 88.
813=28^{\frac{1}{3}} = 2
The exponent of 13\frac{1}{3} represents the cube root, and 23=82^3 = 8.
3
Simplify the variable term using the power of a power rule, (xa)b=xab(x^a)^b = x^{a \cdot b}.
(x6)13=x613=x2(x^6)^{\frac{1}{3}} = x^{6 \cdot \frac{1}{3}} = x^2
Multiplying the exponents simplifies the expression.
4
Multiply the simplified coefficient and variable term together.
2x22x^2
This gives the final simplified equivalent expression.

Anahtar Kavram

Simplifying algebraic expressions with fractional exponents using exponent rules.
Soru 1320Soru

Although a colony of leafcutter ants can consist of millions of individual workers, _______ functions as a superorganism, coordinating complex foraging routes to harvest vegetation.

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

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Cevap: it

Cevap

The singular subject pronoun 'it' correctly completes the sentence by agreeing in number with the singular antecedent 'colony' and serving as the subject of the clause.
The correct option is the singular subject pronoun 'it'. The pronoun refers back to the singular collective noun 'colony', not the plural nouns 'ants' or 'workers' within the prepositional phrases. Therefore, a singular pronoun is required. Additionally, because the pronoun serves as the subject of the verb 'functions', it must be in the subject case rather than the possessive case.

Adım Adım Çözüm

1
Identify the antecedent of the blank space.
The antecedent is the singular noun phrase 'a colony of leafcutter ants,' where the main noun is the singular collective noun 'colony.'
Finding the noun being replaced by the pronoun determines whether the pronoun must be singular or plural.
2
Determine the grammatical function of the pronoun in the clause.
The pronoun precedes the verb 'functions' and acts as the subject of the independent clause.
Knowing the function of the pronoun helps identify the correct case (subject vs. object or possessive).
3
Select the pronoun that matches both the singular number of the antecedent and the subject case.
The singular subject pronoun 'it' fits both requirements, while plural options like 'they' and 'their' or possessive options like 'its' do not.
Standard English conventions require agreement in both number and grammatical case.

Anahtar Kavram

Pronoun-Antecedent Agreement and Case
ÖncekiSayfa 66 / 140Sonraki
Tüm alıştırma soruları — SAT | Examkin