SOLUTION: Please help!! (x+8)^2 +15(x+8) +54 = 0

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Question 870118: Please help!!
(x+8)^2 +15(x+8) +54 = 0
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
(x+8)^2 +15(x+8) +54 = 0
let u=(x+8)
u^2+15u+54=0
(u+9)(u+6)=0
..
u=-9=x+8
x=-17
..
u=-6=x+8
x=-14
..
Check:
f(-17)=(x+8)^2 +15(x+8) +54
=(-17+8)^2 +15(-17+8) +54=0
..
f(-14)=(x+8)^2 +15(x+8) +54
=(-14+8)^2+15(-14+8)+54=0
check ok