SOLUTION: Evaluate (-x) square and -x square when x= 10 and x= -10

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Question 220688: Evaluate (-x) square and -x square when x= 10 and x= -10
Answer by jsmallt9(3759) About Me  (Show Source):
You can put this solution on YOUR website!
An important lesson to learn about exponents is that an exponent applies only to what is immediately in front of it

With %28-x%29%5E2 it is the right parenthesis, ")", that is immediately in front of the exponent. Therefore exponent applies to the entire expression in the parentheses. So %28-x%29%5E2+=+%28-x%29%28-x%29.

With -x%5E2 it is the x that is immediately in front of the exponent. Therefore the exponent applies only to the x. So -x%5E2+=+-x%2Ax

Now that we understand the differences in the two expressions we can correctly evaluate them for the given values of x:
x = 10
   %28-x%29%5E2+=+%28-%2810%29%29%5E2+=+%28-10%29%5E2+=+%28-10%29%2A%28-10%29+=+100
   -x%5E2+=+-%2810%29%5E2+=+-%2810%2A10%29+=+-%28100%29+=+-100
x = -10
   %28-x%29%5E2+=+%28-%28-10%29%29%5E2+=+%2810%29%5E2+=+%2810%29%2A%2810%29+=+100
   -x%5E2+=+-%28-10%29%5E2+=+-%28%28-10%29%2A%28-10%29%29+=+-%28100%29+=+-100