SOLUTION: how do i solve the quadratic equasion x^2+11x-80=0

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Question 174686: how do i solve the quadratic equasion x^2+11x-80=0
Found 2 solutions by stanbon, josmiceli:
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
solve the quadratic equasion x^2+11x-80=0
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Factor:
(x+16)(x-5) = 0
x = -16 or x = 5
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Cheers,
Stan H.

Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!
I like to use the method called "completing the square"
To do this you first get the constant term on the
other side
(1) Add to both sides

(2) Now divide the coefficient of the x term by ,
then square it and add this to both sides

The purpose of this is to make the left side a perfect
square, which it is. It might be hard to see, but I
can rewrite this as

Now I want to express as

Now take the square root of both sides

and

check answers:

OK

OK