75=16t2

Solution for 75=16t2 equation:

75=16t^2

We move all terms to the left:

75-(16t^2)=0

a = -16; b = 0; c = +75;
Δ = b2-4ac
Δ = 02-4·(-16)·75
Δ = 4800
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:

$\sqrt{\Delta}=\sqrt{4800}=\sqrt{1600*3}=\sqrt{1600}*\sqrt{3}=40\sqrt{3}$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-40\sqrt{3}}{2*-16}=\frac{0-40\sqrt{3}}{-32}
=-\frac{40\sqrt{3}}{-32}
=-\frac{5\sqrt{3}}{-4}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+40\sqrt{3}}{2*-16}=\frac{0+40\sqrt{3}}{-32}
=\frac{40\sqrt{3}}{-32}
=\frac{5\sqrt{3}}{-4}
$