10
AssignmentLong Text

Simplifying Expressions

Question 10 • AJH Pre-Algebra A (Grade 8)

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

Answer:

Amir made a mistake in the order of operations. He distributed the negative sign before evaluating the exponent, or treated the subtraction as part of the base being squared. According to PEMDAS, he should have added the numbers inside the parentheses first (2 + 3 = 5), then squared that result (5^2 = 25), and finally subtracted it from 10. The correct calculation is 10 - 25 = -15.

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