SOLUTION: the square root of x-4 - the square root of x+8 =2

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Question 131441: the square root of x-4 - the square root of x+8 =2
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt(x-4)-sqrt(x+8)=2
sqrt(x-4)-2=sqrt(x+8)
x-4-4sqrt(x-4)+4=x+8 square both sides.
-4sqrt(x-4)=8
(-4sqrt(x-4))^2=8^2
16(x-4)=64
16x-64=64
16x=128
x=8
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Check:
sqrt(8-4)-sqrt(8+8)=2
2-4=2 False
There is no answer to this equation.
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Ed