63.25=64t-16t^2

Solution for 63.25=64t-16t^2 equation:

63.25=64t-16t^2

We move all terms to the left:

63.25-(64t-16t^2)=0

We get rid of parentheses

16t^2-64t+63.25=0

a = 16; b = -64; c = +63.25;
Δ = b2-4ac
Δ = -642-4·16·63.25
Δ = 48
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{48}=\sqrt{16*3}=\sqrt{16}*\sqrt{3}=4\sqrt{3}$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-64)-4\sqrt{3}}{2*16}=\frac{64-4\sqrt{3}}{32}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-64)+4\sqrt{3}}{2*16}=\frac{64+4\sqrt{3}}{32}
$