13x2-13x-15=0

Solution for 13x2-13x-15=0 equation:

13x^2-13x-15=0

a = 13; b = -13; c = -15;
Δ = b2-4ac
Δ = -132-4·13·(-15)
Δ = 949
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{-(-13)-\sqrt{949}}{2*13}=\frac{13-\sqrt{949}}{26}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-13)+\sqrt{949}}{2*13}=\frac{13+\sqrt{949}}{26}
$