(-4.9t)(-4.9t)+39.2t=0

Solution for (-4.9t)(-4.9t)+39.2t=0 equation:

(-4.9t)(-4.9t)+39.2t=0

We add all the numbers together, and all the variables

39.2t+(-4.9t)(-4.9t)=0

We multiply parentheses ..

(+16t^2)+39.2t=0

We get rid of parentheses

16t^2+39.2t=0

a = 16; b = 39.2; c = 0;
Δ = b2-4ac
Δ = 39.22-4·16·0
Δ = 1536.64
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{-(39.2)-\sqrt{1536.64}}{2*16}=\frac{-39.2-\sqrt{1536.64}}{32}
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(39.2)+\sqrt{1536.64}}{2*16}=\frac{-39.2+\sqrt{1536.64}}{32}
$