SOLUTION: I need to solve the equation square root of x+56=x and i ned to check for extraneous solutions

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Question 33768: I need to solve the equation square root of x+56=x and i ned to check for extraneous solutions
Answer by venugopalramana(3286) About Me  (Show Source):
You can put this solution on YOUR website!
square root of x+56=x....SQUARING
X+56=X^2
X^2-X-56=0=X^2-8X+7X-56=X(X-8)+7(X-8)=(X-8)(X+7)=0
X=8...OR...-7...CHECKING BACK WE GET
SQRT(8+56)=SQRT(64)=8=X...OK
SQRT(-7+56)=SQRT(49)=7=-X..SO NOT CORRECT...
HENCE ONLY X=8 IS CORRECT SOLUTION