(26-y)*y=24

Solution for (26-y)*y=24 equation:

(26-y)*y=24

We move all terms to the left:

(26-y)*y-(24)=0

We add all the numbers together, and all the variables

(-1y+26)*y-24=0

We multiply parentheses

-1y^2+26y-24=0

a = -1; b = 26; c = -24;
Δ = b2-4ac
Δ = 262-4·(-1)·(-24)
Δ = 580
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{580}=\sqrt{4*145}=\sqrt{4}*\sqrt{145}=2\sqrt{145}$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(26)-2\sqrt{145}}{2*-1}=\frac{-26-2\sqrt{145}}{-2}
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(26)+2\sqrt{145}}{2*-1}=\frac{-26+2\sqrt{145}}{-2}
$