Y=x2-7x-60

Solution for Y=x2-7x-60 equation:

=Y2-7Y-60

We move all terms to the left:

-(Y2-7Y-60)=0

We add all the numbers together, and all the variables

-(+Y^2-7Y-60)=0

We get rid of parentheses

-Y^2+7Y+60=0

We add all the numbers together, and all the variables

-1Y^2+7Y+60=0

a = -1; b = 7; c = +60;
Δ = b2-4ac
Δ = 72-4·(-1)·60
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{-(7)-17}{2*-1}=\frac{-24}{-2}
=+12
$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(7)+17}{2*-1}=\frac{10}{-2}
=-5
$