SOLUTION: When a number x is added to its square, the total is 90. find the values of x.

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Question 721712: When a number x is added to its square, the total is 90. find the values of x.
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
if "a number" is x, then its square would be x%5E2. And "When a number x is added to its square, the total is 90" translates into:
x+%2B+x%5E2+=+90

This is a quadratic equation so we want it in standard form. Subtracting 90 and rearranging the terms we get:
x%5E2%2Bx-90=0
Factor:
(x+10)(x-9) = 0
From the Zero Product Property we get:
x+10 = 0 or x-9 = 0
Solving these:
x = -10 or x = 9
These are both solutions to the problem. Check them if you like.