Mathematics > Standard Multiple Choice

Read the following SAT test question and then click on a button to select your answer.

First, 3 is subtracted from x and the square root of the difference is taken. Then, 5 is added to the result, giving a final result of 9. What is the value of x?

A. 3

B. 4

C. 5

D. 16

E. 19

The correct answer is E

Explanation

When 3 is subtracted from x, the result is x minus 3. The square root of this difference is square root (x minus 3). When 5 is added to square root (x minus 3), the final result is 9. This can be written as (square root (x minus 3)) plus 5 = 9. Subtracting 5 from both sides gives the equation square root (x minus 3) = 4. Squaring both sides of this equation gives x minus 3 = 16, or x = 19.