-7y(y-12)=-147

Solution for -7y(y-12)=-147 equation:

-7y(y-12)=-147

We move all terms to the left:

-7y(y-12)-(-147)=0

We add all the numbers together, and all the variables

-7y(y-12)+147=0

We multiply parentheses

-7y^2+84y+147=0

a = -7; b = 84; c = +147;
Δ = b2-4ac
Δ = 842-4·(-7)·147
Δ = 11172
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:

$\sqrt{\Delta}=\sqrt{11172}=\sqrt{196*57}=\sqrt{196}*\sqrt{57}=14\sqrt{57}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(84)-14\sqrt{57}}{2*-7}=\frac{-84-14\sqrt{57}}{-14}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(84)+14\sqrt{57}}{2*-7}=\frac{-84+14\sqrt{57}}{-14}
$