2x2-3x=15

Solution for 2x2-3x=15 equation:

2x^2-3x=15

We move all terms to the left:

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

a = 2; b = -3; c = -15;
Δ = b2-4ac
Δ = -32-4·2·(-15)
Δ = 129
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{129}}{2*2}=\frac{3-\sqrt{129}}{4}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-3)+\sqrt{129}}{2*2}=\frac{3+\sqrt{129}}{4}
$