-16t2-90t-126=0

Solution for -16t2-90t-126=0 equation:

-16t^2-90t-126=0

a = -16; b = -90; c = -126;
Δ = b2-4ac
Δ = -902-4·(-16)·(-126)
Δ = 36
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{36}=6$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-90)-6}{2*-16}=\frac{84}{-32}
=-2+5/8
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-90)+6}{2*-16}=\frac{96}{-32}
=-3
$