-3y*4y=(4+5y)-72

Solution for -3y*4y=(4+5y)-72 equation:

-3y*4y=(4+5y)-72

We move all terms to the left:

-3y*4y-((4+5y)-72)=0

We add all the numbers together, and all the variables

-3y*4y-((5y+4)-72)=0

Wy multiply elements

-12y^2-((5y+4)-72)=0


We calculate terms in parentheses: -((5y+4)-72), so:

(5y+4)-72

We get rid of parentheses

5y+4-72

We add all the numbers together, and all the variables

5y-68

Back to the equation:

-(5y-68)


We get rid of parentheses

-12y^2-5y+68=0

a = -12; b = -5; c = +68;
Δ = b2-4ac
Δ = -52-4·(-12)·68
Δ = 3289
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{-(-5)-\sqrt{3289}}{2*-12}=\frac{5-\sqrt{3289}}{-24}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-5)+\sqrt{3289}}{2*-12}=\frac{5+\sqrt{3289}}{-24}
$