SATs Algebraic Expressions & Equations 3

Question 1

The sum of three consecutive integers is 57. What is the largest of the three integers?

Accepted Answer

19

Answer

Let the integers be n, n+1, n+2; then 3n + 3 = 57, so n = 18 and the largest is 20.

Question 2

Which of the following is equivalent to (3x² − 2x + 5) − (x² + 4x − 3)?

Accepted Answer

2x² − 6x + 8

Answer

Distributing the minus sign: (3x²−x²) + (−2x−4x) + (5+3) = 2x² − 6x + 8.

Question 3

If 5 − 2x > 11, which of the following must be true?

Accepted Answer

x < −3

Answer

Subtracting 5: −2x > 6; dividing by −2 and flipping: x < −3.

Question 4

What is the product of (2x + 3) and (x − 4)?

Accepted Answer

2x² − 5x − 12

Answer

FOIL: 2x·x + 2x·(−4) + 3·x + 3·(−4) = 2x² − 8x + 3x − 12 = 2x² − 5x − 12.

Question 5

If y = 3x − 7 and y = 5, what is x?

Accepted Answer

4

Answer

Substituting: 3x − 7 = 5, so 3x = 12, giving x = 4.

SATs (Standard Assessment Test) Practice Test