15x^2+7x-88=0

Solution for 15x^2+7x-88=0 equation:

15x^2+7x-88=0

a = 15; b = 7; c = -88;
Δ = b2-4ac
Δ = 72-4·15·(-88)
Δ = 5329
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{5329}=73$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(7)-73}{2*15}=\frac{-80}{30}
=-2+2/3
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(7)+73}{2*15}=\frac{66}{30}
=2+1/5
$