0=-4.9x^2+6.8x+3

Solution for 0=-4.9x^2+6.8x+3 equation:

0=-4.9x^2+6.8x+3

We move all terms to the left:

0-(-4.9x^2+6.8x+3)=0

We add all the numbers together, and all the variables

-(-4.9x^2+6.8x+3)=0

We get rid of parentheses

4.9x^2-6.8x-3=0

a = 4.9; b = -6.8; c = -3;
Δ = b2-4ac
Δ = -6.82-4·4.9·(-3)
Δ = 105.04
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{-(-6.8)-\sqrt{105.04}}{2*4.9}=\frac{6.8-\sqrt{105.04}}{9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-6.8)+\sqrt{105.04}}{2*4.9}=\frac{6.8+\sqrt{105.04}}{9.8}
$