SOLUTION: I do not really understand how to do this... sqrt(3x+17) - 5 = x

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Question 570598: I do not really understand how to do this...
sqrt(3x+17) - 5 = x

Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
sqrt%283x%2B17%29+-+5+=+x
sqrt%283x%2B17%29+=+x%2B5
square both side of the equation
3x%2B17+=+%28x%2B5%29%5E2

3x%2B17+=+x%5E2%2B10x%2B25

x^2+7x+8=0
Find the roots of the equation by quadratic formula

a= 1 b= 7 c= 8

b^2-4ac= 49 - -32
b^2-4ac= 17
sqrt%28%0917%09%29= 4.12
x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=( -7 + 4.12 )/ 2
x1= -1.44

x2=( -7 -4.12 ) / 2
x2= -5.56