SOLUTION: Solve by completing the square. x^2 – 16x + 63 = 0

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Question 104542: Solve by completing the square.
x^2 – 16x + 63 = 0
Found 2 solutions by edjones, Fombitz:
Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
x^2–16x+63=0
x^2-16x =-63
x^2-16x+64=1 add (16/2)^2 to both sides
(x-8)^2=1 factor
x-8= +-1
x=8+1, x=8-1
x=9, x=7
Ed

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2-16x%2B63=0
To complete the square, you want to find the form
%28x%2Ba%29%5E2=x%5E2%2B2ax%2Ba%5E2
By comparing the expanded perfect square equation to your equation, you see that,
2ax=-16x
a=-8
a%5E2=64
I have 63, so I just need to add 1, to have a perfect square form on the left hand side.
x%5E2-16x%2B63%2B1=1
x%5E2-16x%2B64=1
%28x-8%29%5E2=1
sqrt%28%28x-8%29%5E2%29=sqrt%281%29
Since sqrt%281%29=1 and sqrt%281%29=-1, we will solve for two solutions.
First,
x-8=1
x=9
Secnd
x-8=-1
x=7
Let's verify the solutions.
x%5E2-16x%2B63=0
9%5E2-16%289%29%2B63=0
81-144%2B63=0
0=0
Good answer.
x%5E2-16x%2B63=0
7%5E2-16%287%29%2B63=0
49-112%2B63=0
0=0
Good answer.