SOLUTION: The square of a number plus twice the number is 120. Find the number(s).

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Question 760285: The square of a number plus twice the number is 120. Find the number(s).
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
number = x
x^2 + 2x = 120
x^2 + 2x - 120 = 0
Factorise.
(x - 10)(x + 12) = 0
x = -12
x = 10
Your number is 10 or -12
Hope this helps.
:-)