4.9t^2-13.5t-17=0

Solution for 4.9t^2-13.5t-17=0 equation:

4.9t^2-13.5t-17=0

a = 4.9; b = -13.5; c = -17;
Δ = b2-4ac
Δ = -13.52-4·4.9·(-17)
Δ = 515.45
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{-(-13.5)-\sqrt{515.45}}{2*4.9}=\frac{13.5-\sqrt{515.45}}{9.8}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-13.5)+\sqrt{515.45}}{2*4.9}=\frac{13.5+\sqrt{515.45}}{9.8}
$