SOLUTION: Can you please help me out on this: Sqrt (x^2 + 10x -3) = 2x

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Question 1033565: Can you please help me out on this:
Sqrt (x^2 + 10x -3) = 2x
Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
Square left and right members.

x%5E2%2B10x-3=4x%5E2

Simplify.
x%5E2-4x%5E2%2B10x-3=0
-3x%5E2%2B10x-3=0
3x%5E2-10x%2B3=0

Find the discriminant in preparation for general solution formula of quadratic equation.
D=100-4%2A3%2A3
D=100-36
D=64
D=8%5E2

General Solution Formula...
x=%2810%2B-+8%29%2F6
x=%285%2B-+4%29%2F3
highlight_green%28system%28x=1%2F3%2Cor%2Cx=3%29%29
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Still not finished.
Will any of these work in the original equation?


PARTIAL CHECK:
Try x at 3.
sqrt%283%5E2%2B10%2A3-3%29=2%2A3
sqrt%289%2B30-3%29=6
sqrt%2836%29=6-------That one seems to work. highlight%28x=3%29 is good.
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Now you still need to check if x=1%2F3 will work.