How do you solve 8(4)squared?

Question

Evaluate:  8x² when x=4

 

Answer 1

Evaluate 8x² when x=4.

What is being tested is if you know that the squared symbol relates only to the x, and not also to the 8.

So, the expression 8x² means 8xx, or (8)(4)(4) which equals 128.

Instead, if you were asked to evaluate (8x)² , that would mean that everything in the parenthesis is being squared.

(8x)² = (8x)(8x) = 64x² and if x=4, then your answer would be (64)(4)(4), which equals 1,024, a very different answer!

Answer 2

When you solve expression with exponents, make sure you follow order of operations.

I your problem multiplication written first but squaring should be calculated first because power has a priority in order of operations.

8×4²=8×16=128

 

Answer 3

This is a simple plug in 4 for x question.  We then have 8*4^{2 =} 8*4*4 = 128.