-4.9t^2+3.8t=-10

Solution for -4.9t^2+3.8t=-10 equation:

-4.9t^2+3.8t=-10

We move all terms to the left:

-4.9t^2+3.8t-(-10)=0

We add all the numbers together, and all the variables

-4.9t^2+3.8t+10=0

a = -4.9; b = 3.8; c = +10;
Δ = b2-4ac
Δ = 3.82-4·(-4.9)·10
Δ = 210.44
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{-(3.8)-\sqrt{210.44}}{2*-4.9}=\frac{-3.8-\sqrt{210.44}}{-9.8}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(3.8)+\sqrt{210.44}}{2*-4.9}=\frac{-3.8+\sqrt{210.44}}{-9.8}
$