6=-4.9t^2+4t+10

Solution for 6=-4.9t^2+4t+10 equation:

6=-4.9t^2+4t+10

We move all terms to the left:

6-(-4.9t^2+4t+10)=0

We get rid of parentheses

4.9t^2-4t-10+6=0

We add all the numbers together, and all the variables

4.9t^2-4t-4=0

a = 4.9; b = -4; c = -4;
Δ = b2-4ac
Δ = -42-4·4.9·(-4)
Δ = 94.4
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{-(-4)-\sqrt{94.4}}{2*4.9}=\frac{4-\sqrt{94.4}}{9.8}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-4)+\sqrt{94.4}}{2*4.9}=\frac{4+\sqrt{94.4}}{9.8}
$