t=-4.9t^2+12t+8

Solution for t=-4.9t^2+12t+8 equation:

t=-4.9t^2+12t+8

We move all terms to the left:

t-(-4.9t^2+12t+8)=0

We get rid of parentheses

4.9t^2-12t+t-8=0

We add all the numbers together, and all the variables

4.9t^2-11t-8=0

a = 4.9; b = -11; c = -8;
Δ = b2-4ac
Δ = -112-4·4.9·(-8)
Δ = 277.8
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{-(-11)-\sqrt{277.8}}{2*4.9}=\frac{11-\sqrt{277.8}}{9.8}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-11)+\sqrt{277.8}}{2*4.9}=\frac{11+\sqrt{277.8}}{9.8}
$