15x^2+8x=-4-8x

Solution for 15x^2+8x=-4-8x equation:

15x^2+8x=-4-8x

We move all terms to the left:

15x^2+8x-(-4-8x)=0

We add all the numbers together, and all the variables

15x^2+8x-(-8x-4)=0

We get rid of parentheses

15x^2+8x+8x+4=0

We add all the numbers together, and all the variables

15x^2+16x+4=0

a = 15; b = 16; c = +4;
Δ = b2-4ac
Δ = 162-4·15·4
Δ = 16
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{16}=4$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(16)-4}{2*15}=\frac{-20}{30}
=-2/3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(16)+4}{2*15}=\frac{-12}{30}
=-2/5
$