-15x^2+12=-8x

Solution for -15x^2+12=-8x equation:

-15x^2+12=-8x

We move all terms to the left:

-15x^2+12-(-8x)=0

We get rid of parentheses

-15x^2+8x+12=0

a = -15; b = 8; c = +12;
Δ = b2-4ac
Δ = 82-4·(-15)·12
Δ = 784
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{784}=28$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(8)-28}{2*-15}=\frac{-36}{-30}
=1+1/5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(8)+28}{2*-15}=\frac{20}{-30}
=-2/3
$