H=4+36t-16t^2

Solution for H=4+36t-16t^2 equation:

=4+36H-16H^2

We move all terms to the left:

-(4+36H-16H^2)=0

We get rid of parentheses

16H^2-36H-4=0

a = 16; b = -36; c = -4;
Δ = b2-4ac
Δ = -362-4·16·(-4)
Δ = 1552
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$H_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$H_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{1552}=\sqrt{16*97}=\sqrt{16}*\sqrt{97}=4\sqrt{97}$
$H_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-36)-4\sqrt{97}}{2*16}=\frac{36-4\sqrt{97}}{32}
$
$H_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-36)+4\sqrt{97}}{2*16}=\frac{36+4\sqrt{97}}{32}
$