2+4x-4.9x^2=0

Solution for 2+4x-4.9x^2=0 equation:

2+4x-4.9x^2=0

a = -4.9; b = 4; c = +2;
Δ = b2-4ac
Δ = 42-4·(-4.9)·2
Δ = 55.2
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{-(4)-\sqrt{55.2}}{2*-4.9}=\frac{-4-\sqrt{55.2}}{-9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(4)+\sqrt{55.2}}{2*-4.9}=\frac{-4+\sqrt{55.2}}{-9.8}
$