Question

HELP!! 100 POINTS!!

Solution: x²-8x-9=0
x²-8x-9=0
x²-8x=9
x²-8x+16=9+16
(x+4)²=25
x-4=25
x=29
x-4=-25
x=-21 Is this solution correct? Please explain in full sentences. I appreciate it!!

Answer 1

x=9 x=-1

Explanation:

x²-8x-9=0 a=1 b=-8 c=-9

you have to use the quadratic formula to get the values.

Answer 2

It's incorrect

x = -1, 9

Explanation:

x²-8x-9=0

x²-8x=9

x²-8x+16=9+16

(x-4)²=25

You have to take square root both sides, so RHS would be sqrt(25) = 5 (+/-)

x-4=+/-5

x-4=5

x-4=-5

x=9

x=-1