19=16x+4.9x^2

Solution for 19=16x+4.9x^2 equation:

19=16x+4.9x^2

We move all terms to the left:

19-(16x+4.9x^2)=0

We get rid of parentheses

-4.9x^2-16x+19=0

a = -4.9; b = -16; c = +19;
Δ = b2-4ac
Δ = -162-4·(-4.9)·19
Δ = 628.4
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-16)-\sqrt{628.4}}{2*-4.9}=\frac{16-\sqrt{628.4}}{-9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-16)+\sqrt{628.4}}{2*-4.9}=\frac{16+\sqrt{628.4}}{-9.8}
$