Y=15x^2+x-28

Solution for Y=15x^2+x-28 equation:

=15Y^2+Y-28

We move all terms to the left:

-(15Y^2+Y-28)=0

We get rid of parentheses

-15Y^2-Y+28=0

We add all the numbers together, and all the variables

-15Y^2-1Y+28=0

a = -15; b = -1; c = +28;
Δ = b2-4ac
Δ = -12-4·(-15)·28
Δ = 1681
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$Y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1681}=41$
$Y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-1)-41}{2*-15}=\frac{-40}{-30}
=1+1/3
$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1)+41}{2*-15}=\frac{42}{-30}
=-1+2/5
$