H=-16t^2+900

Solution for H=-16t^2+900 equation:

=-16H^2+900

We move all terms to the left:

-(-16H^2+900)=0

We get rid of parentheses

16H^2-900=0

a = 16; b = 0; c = -900;
Δ = b2-4ac
Δ = 02-4·16·(-900)
Δ = 57600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$H_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$H_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{57600}=240$
$H_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-240}{2*16}=\frac{-240}{32}
=-7+1/2
$
$H_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+240}{2*16}=\frac{240}{32}
=7+1/2
$