Question

Amir evaluated 5x - (x + 3)2 for x = 2, as shown. Describe Amir's mistake and find the correct answer.

5(2) - (2 + 3)2 = 10 + (-5)2
= 10 + 25
= 35

Answer 1

he never followed the order of operations

Answer 2

By the order of operations, Amir should have squared 5 and then subtracted rather than distributing the negative and squaring.

5(2) - (2 + 3)2 = 10 - (5)2 = 10 - 25 = -15