SOLUTION: Solve. The sq root of (9x+55)=x+5

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Question 224912: Solve.
The sq root of (9x+55)=x+5

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Solve.
sqrt%289x%2B55%29 = x+5
:
Square both sides
9x + 55 = (x+5)^2
:
FOIL the right side
9x + 55 = x^2 + 10x + 25
:
Combine on the right
0 = x^2 + 10x - 9x + 25 - 55
:
x^2 + x - 30 = 0
:
Factors to
(x+6)(x-5) = 0
:
Two solutions
x = -6
and
x = 5
:
Check both solutions in original equation
only x = 5 is valid