PSAT Math Multiple-Choice Question 120: Answer and Explanation

Question: 120

(x - 3)² = 16

Which of the following values of x satisfies the equation above?

• A. -7
• B. -1
• C. 3
• D. 4

Correct Answer: B

Explanation:

B

The question asks for the value of x that satisfies the equation. Since the question asks for a specific value and the answers contain numbers in increasing order, plug in the answers. Begin by labelling the answers as "x" and start with (B), -1. If x = -1, the equation becomes (-1 - 3)² = 16. Subtract within the parentheses to get (-4)² = 16. Square the left side to get 16 = 16. This is true, so stop here. The correct answer is (B).