7y2=4y

Solution for 7y2=4y equation:

7y^2=4y

We move all terms to the left:

7y^2-(4y)=0

a = 7; b = -4; c = 0;
Δ = b2-4ac
Δ = -42-4·7·0
Δ = 16
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{16}=4$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-4)-4}{2*7}=\frac{0}{14}
=0
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-4)+4}{2*7}=\frac{8}{14}
=4/7
$