9y^2+36y-49=0

Solution for 9y^2+36y-49=0 equation:

9y^2+36y-49=0

a = 9; b = 36; c = -49;
Δ = b2-4ac
Δ = 362-4·9·(-49)
Δ = 3060
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{3060}=\sqrt{36*85}=\sqrt{36}*\sqrt{85}=6\sqrt{85}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(36)-6\sqrt{85}}{2*9}=\frac{-36-6\sqrt{85}}{18}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(36)+6\sqrt{85}}{2*9}=\frac{-36+6\sqrt{85}}{18}
$