SOLUTION: five times the square of a certain number is 80.find the number

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Question 639923: five times the square of a certain number is 80.find the number
Answer by josh_jordan(263) About Me  (Show Source):
You can put this solution on YOUR website!
Five times the square of a certain number is 80. In other words:
5x%5E2+=+80
To find x, first divide both sides of the equation by 5:
5x%5E2%2F5+=+80%2F5
This results in
x%5E2+=+16
To get rid of the exponent above the x, take the square root of both sides, since the opposite of "squared" is "square root":
sqrt%28x%5E2%29+=+sqrt%2816%29
This results in
x+=+4
FINAL ANSWER: 4