SOLUTION: when squaring a number and subtracting 6 gives the same result as doubling the number and adding 9

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Question 1017154: when squaring a number and subtracting 6 gives the same result as doubling the number and adding 9
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
Call the number x. Then we write
x^2 - 6 = 2x + 9
Now combine and get
x^2 - 2x - 15 = 0
Factor and solve...
(x - 5)(x + 3) = 0
x = 5 and x = -3
Two solutions.