64t-16t^2=60

Solution for 64t-16t^2=60 equation:

64t-16t^2=60

We move all terms to the left:

64t-16t^2-(60)=0

a = -16; b = 64; c = -60;
Δ = b2-4ac
Δ = 642-4·(-16)·(-60)
Δ = 256
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{256}=16$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(64)-16}{2*-16}=\frac{-80}{-32}
=2+1/2
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(64)+16}{2*-16}=\frac{-48}{-32}
=1+1/2
$