5y+2y(3y+5)-4=100

Solution for 5y+2y(3y+5)-4=100 equation:

5y+2y(3y+5)-4=100

We move all terms to the left:

5y+2y(3y+5)-4-(100)=0

We add all the numbers together, and all the variables

5y+2y(3y+5)-104=0

We multiply parentheses

6y^2+5y+10y-104=0

We add all the numbers together, and all the variables

6y^2+15y-104=0

a = 6; b = 15; c = -104;
Δ = b2-4ac
Δ = 152-4·6·(-104)
Δ = 2721
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{2721}}{2*6}=\frac{-15-\sqrt{2721}}{12}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(15)+\sqrt{2721}}{2*6}=\frac{-15+\sqrt{2721}}{12}
$