15=-16t^2-44t+5

Solution for 15=-16t^2-44t+5 equation:

15=-16t^2-44t+5

We move all terms to the left:

15-(-16t^2-44t+5)=0

We get rid of parentheses

16t^2+44t-5+15=0

We add all the numbers together, and all the variables

16t^2+44t+10=0

a = 16; b = 44; c = +10;
Δ = b2-4ac
Δ = 442-4·16·10
Δ = 1296
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1296}=36$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(44)-36}{2*16}=\frac{-80}{32}
=-2+1/2
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(44)+36}{2*16}=\frac{-8}{32}
=-1/4
$