(8y+6)(18-0.4y)=0

Solution for (8y+6)(18-0.4y)=0 equation:

(8y+6)(18-0.4y)=0

We add all the numbers together, and all the variables

(8y+6)(-0.4y+18)=0

We multiply parentheses ..

(+0y^2+144y+0y+108)=0

We get rid of parentheses

0y^2+144y+0y+108=0

We add all the numbers together, and all the variables

y^2+145y+108=0

a = 1; b = 145; c = +108;
Δ = b2-4ac
Δ = 1452-4·1·108
Δ = 20593
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{-(145)-\sqrt{20593}}{2*1}=\frac{-145-\sqrt{20593}}{2}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(145)+\sqrt{20593}}{2*1}=\frac{-145+\sqrt{20593}}{2}
$