0=6.3+3.3x-4.9x^2

Solution for 0=6.3+3.3x-4.9x^2 equation:

0=6.3+3.3x-4.9x^2

We move all terms to the left:

0-(6.3+3.3x-4.9x^2)=0

We add all the numbers together, and all the variables

-(6.3+3.3x-4.9x^2)=0

We get rid of parentheses

4.9x^2-3.3x-6.3=0

a = 4.9; b = -3.3; c = -6.3;
Δ = b2-4ac
Δ = -3.32-4·4.9·(-6.3)
Δ = 134.37
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{-(-3.3)-\sqrt{134.37}}{2*4.9}=\frac{3.3-\sqrt{134.37}}{9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-3.3)+\sqrt{134.37}}{2*4.9}=\frac{3.3+\sqrt{134.37}}{9.8}
$