4.9t^2-2.3t-25=0

Solution for 4.9t^2-2.3t-25=0 equation:

4.9t^2-2.3t-25=0

a = 4.9; b = -2.3; c = -25;
Δ = b2-4ac
Δ = -2.32-4·4.9·(-25)
Δ = 495.29
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{-(-2.3)-\sqrt{495.29}}{2*4.9}=\frac{2.3-\sqrt{495.29}}{9.8}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-2.3)+\sqrt{495.29}}{2*4.9}=\frac{2.3+\sqrt{495.29}}{9.8}
$