15x^2+25x-510=0

Solution for 15x^2+25x-510=0 equation:

15x^2+25x-510=0

a = 15; b = 25; c = -510;
Δ = b2-4ac
Δ = 252-4·15·(-510)
Δ = 31225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{31225}=\sqrt{25*1249}=\sqrt{25}*\sqrt{1249}=5\sqrt{1249}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(25)-5\sqrt{1249}}{2*15}=\frac{-25-5\sqrt{1249}}{30}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(25)+5\sqrt{1249}}{2*15}=\frac{-25+5\sqrt{1249}}{30}
$