SOLUTION: X^(2)+10x+c=0 how do you factor this?

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Question 393869: X^(2)+10x+c=0
how do you factor this?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2+%2B+10x+%2B+c+=+0
Subtract c from both sides
x%5E2+%2B+10x+=+-c
Take 1/2 of the coefficient of x,
square it, and add it to both sides
x%5E2+%2B+10x+%2B+%2810%2F2%29%5E2+=+-c+%2B+%2810%2F2%29%5E2
x%5E2+%2B+10x+%2B+25+=+-c+%2B+25
The left side is now a perfect square, so rewrite it
%28x+%2B+5%29%5E2+=+25+-+c
Take the square root of both sides
x+%2B+5+=+0++%2B-sqrt%2825+-+c%29
Get all terms on the left side, leaving zero on the right
x+%2B+5+%2B+sqrt%2825+-+c%29
x+%2B+5+-+sqrt%2825+-+c%29
If you multiply these 2 expressions together,
you should get the above equation
You could also have used the quadratic formula
The answers should agree.