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

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The Correct answer is E.

Explanation

When  is subtracted from , the result is . The square root of this difference is . When  is added to , the final result is . This can be written as . Subtracting  from both sides gives the equation . Squaring both sides of this equation gives , or .