SOLUTION: Use the quadratic formula to solve the equation. Give exact answers x^2+2x=8

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Question 734664: Use the quadratic formula to solve the equation. Give exact answers
x^2+2x=8
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
x^2+4x-8
compare with ax^2+bx+c
a=1, b=2,c=-8

b^2-4ac= 4 + 32
b^2-4ac= 36
%09sqrt%28%0936%09%29=%096%09
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=( -2 + 6 )/ 2
x1= 2.00
x2=%28-b-sqrt%28b%5E2-4ac%29%29%2F%282a%29
x2=( -2 -6 ) / 2
x2= -4.00