0=-16t^2+50t-15

Solution for 0=-16t^2+50t-15 equation:

0=-16t^2+50t-15

We move all terms to the left:

0-(-16t^2+50t-15)=0

We add all the numbers together, and all the variables

-(-16t^2+50t-15)=0

We get rid of parentheses

16t^2-50t+15=0

a = 16; b = -50; c = +15;
Δ = b2-4ac
Δ = -502-4·16·15
Δ = 1540
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:

$\sqrt{\Delta}=\sqrt{1540}=\sqrt{4*385}=\sqrt{4}*\sqrt{385}=2\sqrt{385}$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-50)-2\sqrt{385}}{2*16}=\frac{50-2\sqrt{385}}{32}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-50)+2\sqrt{385}}{2*16}=\frac{50+2\sqrt{385}}{32}
$