GRE Algebraic Equations and Functions 2 — Questions and Answers
Question 1: If f(x) = 3x - 7, what is f(4)?
- 5 (Correct answer)
- 12
- 19
- -5
Correct answer: 5
Substitute x = 4: 3(4) - 7 = 12 - 7 = 5.
Question 2: Solve for x: 2x + 5 = 17.
- 4
- 6 (Correct answer)
- 8
- 11
Correct answer: 6
Subtract 5 to get 2x = 12, then divide by 2 to get x = 6.
Question 3: If g(x) = x² + 2x, what is g(-3)?
- 3 (Correct answer)
- -3
- 15
- -15
Correct answer: 3
g(-3) = (-3)² + 2(-3) = 9 - 6 = 3.
Question 4: What is the slope of the line 4x - 2y = 8?
- 2 (Correct answer)
- -2
- 4
- 1/2
Correct answer: 2
Solve for y: y = 2x - 4, so the slope is 2.
Question 5: If 5(x - 2) = 3x + 4, what is x?
- 7 (Correct answer)
- 5
- 3
- -7
Correct answer: 7
Expanding gives 5x - 10 = 3x + 4, so 2x = 14 and x = 7.
Question 6: Which value of x makes the expression (x - 4)/(x + 2) undefined?
- 4
- -2 (Correct answer)
- 2
- 0
Correct answer: -2
A fraction is undefined when its denominator is zero, so x + 2 = 0 gives x = -2.
Question 7: If h(x) = 2x + 1 and h(a) = 9, what is a?
- 4 (Correct answer)
- 5
- 3
- 8
Correct answer: 4
2a + 1 = 9 gives 2a = 8, so a = 4.
GRE Algebraic Equations and Functions 2
If f(x) = 3x - 7, what is f(4)?