0=8x^2+15x-2

Solution for 0=8x^2+15x-2 equation:

0=8x^2+15x-2

We move all terms to the left:

0-(8x^2+15x-2)=0

We add all the numbers together, and all the variables

-(8x^2+15x-2)=0

We get rid of parentheses

-8x^2-15x+2=0

a = -8; b = -15; c = +2;
Δ = b2-4ac
Δ = -152-4·(-8)·2
Δ = 289
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{289}=17$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-15)-17}{2*-8}=\frac{-2}{-16}
=1/8
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-15)+17}{2*-8}=\frac{32}{-16}
=-2
$