2x2-3x-15=15

Solution for 2x2-3x-15=15 equation:

2x^2-3x-15=15

We move all terms to the left:

2x^2-3x-15-(15)=0

We add all the numbers together, and all the variables

2x^2-3x-30=0

a = 2; b = -3; c = -30;
Δ = b2-4ac
Δ = -32-4·2·(-30)
Δ = 249
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-3)-\sqrt{249}}{2*2}=\frac{3-\sqrt{249}}{4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-3)+\sqrt{249}}{2*2}=\frac{3+\sqrt{249}}{4}
$