50=4.9x^2

Solution for 50=4.9x^2 equation:

50=4.9x^2

We move all terms to the left:

50-(4.9x^2)=0

We get rid of parentheses

-4.9x^2+50=0

a = -4.9; b = 0; c = +50;
Δ = b2-4ac
Δ = 02-4·(-4.9)·50
Δ = 980
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

The end solution:

$\sqrt{\Delta}=\sqrt{980}=\sqrt{4*245}=\sqrt{4}*\sqrt{245}=2\sqrt{245}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-2\sqrt{245}}{2*-4.9}=\frac{0-2\sqrt{245}}{-9.8}
=-\frac{2\sqrt{245}}{-9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+2\sqrt{245}}{2*-4.9}=\frac{0+2\sqrt{245}}{-9.8}
=\frac{2\sqrt{245}}{-9.8}
$