25x2+25x-36=0

Solution for 25x2+25x-36=0 equation:

25x^2+25x-36=0

a = 25; b = 25; c = -36;
Δ = b2-4ac
Δ = 252-4·25·(-36)
Δ = 4225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4225}=65$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(25)-65}{2*25}=\frac{-90}{50}
=-1+4/5
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(25)+65}{2*25}=\frac{40}{50}
=4/5
$