SOLUTION: x2 + 8x = 3

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Question 246072: x2 + 8x = 3
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
assuming you mean
x^2+8x=3
we need to complete the square or use the quadratic formula.
take (8/2)^2=4^2=16
add 16 to both sides
x^2+8x+16=19
factor left side
(x+4)^2=19
get sqrts
|x+4|=sqrt(19)
x+4=+sqrt(19)
x+4=-sqrt(19)
subtract four from both sides
x=-4-sqrt(19) or x=-4+sqrt(19)