-1.7t^2+12t+75=0

Solution for -1.7t^2+12t+75=0 equation:

-1.7t^2+12t+75=0

a = -1.7; b = 12; c = +75;
Δ = b2-4ac
Δ = 122-4·(-1.7)·75
Δ = 654
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(12)-\sqrt{654}}{2*-1.7}=\frac{-12-\sqrt{654}}{-3.4}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(12)+\sqrt{654}}{2*-1.7}=\frac{-12+\sqrt{654}}{-3.4}
$