SOLUTION: how do i evaluate the expression 5x3 to the negative 3rd power?

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Question 346277: how do i evaluate the expression 5x3 to the negative 3rd power?
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
I think you mean "How do I simplify...". Evaluating is when you replace one or more variables with numbers and then simplify. There are no variables in your expression.

5%2A3%5E%28-3%29
Accorsing to the order of operations (aka PEMDAS), we should simplify exponents before mutiplying. In order to raise 3 to the -3 power we need to remember what a negative exponent means. A negative exponent means a reciprocal. In general:
x%5E%28-n%29+=+%28x%2F1%29%5E%28-n%29+=+1%2Fx%5En
So 3^(-3) = 1/3^3 = 1/3*3*3 = 1/27. So we can replace 3%5E%28-3%29 with 1/27:
5%2A%281%2F27%29
Now we can multiply:
5%2F27
And we're finished.