SOLUTION: How to use the Quadratic Formula to solve x^2 - 8x = 20.

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Question 541193: How to use the Quadratic Formula to solve x^2 - 8x = 20.
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
x^2-8x=20
x^-8x-20=0
Find the roots of the equation by quadratic formula

a= 1 ,b= -8 ,c= -20
b^2-4ac=
b^2-4ac= 64 - 80
b^2-4ac= 144
sqrt%28%09144%09%29= 12
x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=( 8 + 12 )/ 2
x1= 10
x2=( 8 -12 ) / 2
x2= -2