4.9t^2+345t=621

Solution for 4.9t^2+345t=621 equation:

4.9t^2+345t=621

We move all terms to the left:

4.9t^2+345t-(621)=0

a = 4.9; b = 345; c = -621;
Δ = b2-4ac
Δ = 3452-4·4.9·(-621)
Δ = 131196.6
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{-(345)-\sqrt{131196.6}}{2*4.9}=\frac{-345-\sqrt{131196.6}}{9.8}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(345)+\sqrt{131196.6}}{2*4.9}=\frac{-345+\sqrt{131196.6}}{9.8}
$