9a^2=-27a-20

Solution for 9a^2=-27a-20 equation:

9a^2=-27a-20

We move all terms to the left:

9a^2-(-27a-20)=0

We get rid of parentheses

9a^2+27a+20=0

a = 9; b = 27; c = +20;
Δ = b2-4ac
Δ = 272-4·9·20
Δ = 9
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{9}=3$
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(27)-3}{2*9}=\frac{-30}{18}
=-1+2/3
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(27)+3}{2*9}=\frac{-24}{18}
=-1+1/3
$