50t-5t^2-80=0

Solution for 50t-5t^2-80=0 equation:

50t-5t^2-80=0

a = -5; b = 50; c = -80;
Δ = b2-4ac
Δ = 502-4·(-5)·(-80)
Δ = 900
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{900}=30$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(50)-30}{2*-5}=\frac{-80}{-10}
=+8
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(50)+30}{2*-5}=\frac{-20}{-10}
=+2
$