0=-1.9t^2+56t+30

Solution for 0=-1.9t^2+56t+30 equation:

0=-1.9t^2+56t+30

We move all terms to the left:

0-(-1.9t^2+56t+30)=0

We add all the numbers together, and all the variables

-(-1.9t^2+56t+30)=0

We get rid of parentheses

1.9t^2-56t-30=0

a = 1.9; b = -56; c = -30;
Δ = b2-4ac
Δ = -562-4·1.9·(-30)
Δ = 3364
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3364}=58$
$t_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-56)-58}{2*1.9}=\frac{-2}{3.8}
=-2/3.8
$
$t_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-56)+58}{2*1.9}=\frac{114}{3.8}
=30
$