25n^2+75n=-56

Solution for 25n^2+75n=-56 equation:

25n^2+75n=-56

We move all terms to the left:

25n^2+75n-(-56)=0

We add all the numbers together, and all the variables

25n^2+75n+56=0

a = 25; b = 75; c = +56;
Δ = b2-4ac
Δ = 752-4·25·56
Δ = 25
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{25}=5$
$n_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(75)-5}{2*25}=\frac{-80}{50}
=-1+3/5
$
$n_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(75)+5}{2*25}=\frac{-70}{50}
=-1+2/5
$