1.25t^2-11.11t-11.11=0

Solution for 1.25t^2-11.11t-11.11=0 equation:

1.25t^2-11.11t-11.11=0

a = 1.25; b = -11.11; c = -11.11;
Δ = b2-4ac
Δ = -11.112-4·1.25·(-11.11)
Δ = 178.9821
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{-(-11.11)-\sqrt{178.9821}}{2*1.25}=\frac{11.11-\sqrt{178.9821}}{2.5}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-11.11)+\sqrt{178.9821}}{2*1.25}=\frac{11.11+\sqrt{178.9821}}{2.5}
$