36x^2+18x-28=0

Solution for 36x^2+18x-28=0 equation:

36x^2+18x-28=0

a = 36; b = 18; c = -28;
Δ = b2-4ac
Δ = 182-4·36·(-28)
Δ = 4356
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4356}=66$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(18)-66}{2*36}=\frac{-84}{72}
=-1+1/6
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(18)+66}{2*36}=\frac{48}{72}
=2/3
$