Y=m2-13m-30

Solution for Y=m2-13m-30 equation:

=Y2-13Y-30

We move all terms to the left:

-(Y2-13Y-30)=0

We add all the numbers together, and all the variables

-(+Y^2-13Y-30)=0

We get rid of parentheses

-Y^2+13Y+30=0

We add all the numbers together, and all the variables

-1Y^2+13Y+30=0

a = -1; b = 13; c = +30;
Δ = b2-4ac
Δ = 132-4·(-1)·30
Δ = 289
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$Y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{289}=17$
$Y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(13)-17}{2*-1}=\frac{-30}{-2}
=+15
$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(13)+17}{2*-1}=\frac{4}{-2}
=-2
$