4.9=14.10t-4.91t^2

Solution for 4.9=14.10t-4.91t^2 equation:

4.9=14.10t-4.91t^2

We move all terms to the left:

4.9-(14.10t-4.91t^2)=0

We get rid of parentheses

4.91t^2-14.10t+4.9=0

We add all the numbers together, and all the variables

4.91t^2-14.1t+4.9=0

a = 4.91; b = -14.1; c = +4.9;
Δ = b2-4ac
Δ = -14.12-4·4.91·4.9
Δ = 102.574
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{-(-14.1)-\sqrt{102.574}}{2*4.91}=\frac{14.1-\sqrt{102.574}}{9.82}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-14.1)+\sqrt{102.574}}{2*4.91}=\frac{14.1+\sqrt{102.574}}{9.82}
$