Mathematics > Standard Multiple Choice
Read the following SAT test question and then click on a button to select your answer.
If and , then
(A) 4
(B) 8
(C) 15
(D) 16
(E) 64
The Correct answer is C.
Explanation
Recall that can be factored as . Since and , their product, , is , or .
Another method of solution is to solve the two equations and simultaneously to get and . Then is .