15x^2+7x-20=-20

Solution for 15x^2+7x-20=-20 equation:

15x^2+7x-20=-20

We move all terms to the left:

15x^2+7x-20-(-20)=0

We add all the numbers together, and all the variables

15x^2+7x=0

a = 15; b = 7; c = 0;
Δ = b2-4ac
Δ = 72-4·15·0
Δ = 49
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{49}=7$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(7)-7}{2*15}=\frac{-14}{30}
=-7/15
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(7)+7}{2*15}=\frac{0}{30}
=0
$