-4.9t^2=-5t-209

Solution for -4.9t^2=-5t-209 equation:

-4.9t^2=-5t-209

We move all terms to the left:

-4.9t^2-(-5t-209)=0

We get rid of parentheses

-4.9t^2+5t+209=0

a = -4.9; b = 5; c = +209;
Δ = b2-4ac
Δ = 52-4·(-4.9)·209
Δ = 4121.4
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{-(5)-\sqrt{4121.4}}{2*-4.9}=\frac{-5-\sqrt{4121.4}}{-9.8}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(5)+\sqrt{4121.4}}{2*-4.9}=\frac{-5+\sqrt{4121.4}}{-9.8}
$