-4.9x^2-7.22x+1.3=0

Solution for -4.9x^2-7.22x+1.3=0 equation:

-4.9x^2-7.22x+1.3=0

a = -4.9; b = -7.22; c = +1.3;
Δ = b2-4ac
Δ = -7.222-4·(-4.9)·1.3
Δ = 77.6084
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{-(-7.22)-\sqrt{77.6084}}{2*-4.9}=\frac{7.22-\sqrt{77.6084}}{-9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-7.22)+\sqrt{77.6084}}{2*-4.9}=\frac{7.22+\sqrt{77.6084}}{-9.8}
$