.3y^2+.15y+-11.7=0

Solution for .3y^2+.15y+-11.7=0 equation:

.3y^2+.15y+-11.7=0

We add all the numbers together, and all the variables

.3y^2+.15y=0

a = .3; b = .15; c = 0;
Δ = b2-4ac
Δ = .152-4·.3·0
Δ = 0.0225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(.15)-\sqrt{0.0225}}{2*.3}=\frac{-0.15-\sqrt{0.0225}}{0.6}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(.15)+\sqrt{0.0225}}{2*.3}=\frac{-0.15+\sqrt{0.0225}}{0.6}
$