Question

A student says that if 5x2 = 20, then x must be

equal to 2. Do you agree or disagree with the
student? Justify your answer.

Answer 1

No I feel like it will = 4 because 5 x 4=20

Answer 2

Sample answer:

I disagree. If each side of the equation is divided by 5, the result is x2 = 4. By the square root property of equality, x = -2 or x = 2. So x could be -2 instead of 2.