1.2t2-3.5t-7=0

Solution for 1.2t2-3.5t-7=0 equation:

1.2t^2-3.5t-7=0

a = 1.2; b = -3.5; c = -7;
Δ = b2-4ac
Δ = -3.52-4·1.2·(-7)
Δ = 45.85
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{-(-3.5)-\sqrt{45.85}}{2*1.2}=\frac{3.5-\sqrt{45.85}}{2.4}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-3.5)+\sqrt{45.85}}{2*1.2}=\frac{3.5+\sqrt{45.85}}{2.4}
$