Question

Solve the equation by graphing:-8x^3-13x^2+6x=0
a.no solution
b.-2,.38
c.0,2,-.38
d.0,-2,.38

Answer 1

1. divide the whole thing by x
-8x^2-13x+6=0
-8x^2-16x+3x+6=0
-8x(x+2)+3(x+2)=0
(-8x+3)(x+2)=0
x1=3\8
x2=-2

Answer 2

\[-8x^3-13x^2+6x = x (-8x^2 - 13x + 6)\]
Then you have to use the quadratic formula to find the other two roots (one of the roots is x = 0)