SOLUTION: how do i solve 3x^2-5x-8=0 using the quadratic formula

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Question 733212: how do i solve 3x^2-5x-8=0 using the quadratic formula
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
3x%5E2-5x-8=0
compare with equation ax%5E2%2Bbx%2Bc=0

a= 3 , b= -5 , c= -8

b^2-4ac= 25 + 96
b^2-4ac= 121
%09sqrt%28%09121%09%29=%0911%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=( 5 + 11 )/ 6
x1= 2.67
x2=%28-b-sqrt%28b%5E2-4ac%29%29%2F%282a%29
x2=( 5 -11 ) / 6
x2= -1.00

2.67 , -1

m.ananth@hotmail.ca