SOLUTION: solve by using the quadratic formula x squared minus two x equals 80 how do you solve this

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Question 617744: solve by using the quadratic formula x squared minus two x equals 80 how do you solve this
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
this can be solved by factoring.
you need to put it in standard form of ax^2 + bx + c = 0
do that by subtracting 80 from both sides of the equation.
you start with:
x^2 - 2x = 80
subtract 80 from both sides to get:
x^2 - 2x - 80 = 0
factor this to get:
(x-10) * (x+8) = 0
the roots of this equation are:
x = 10 and x = -8
graph of this equation looks like this:
graph%28600%2C600%2C-12%2C12%2C-100%2C12%2Cx%5E2+-+2x+-+80%29
the solutions to the equation are at x = 10 and x = -8
this is shown on the graph where the equation crosses the x-axis.