9.8x^2=100

Solution for 9.8x^2=100 equation:

9.8x^2=100

We move all terms to the left:

9.8x^2-(100)=0

a = 9.8; b = 0; c = -100;
Δ = b2-4ac
Δ = 02-4·9.8·(-100)
Δ = 3920
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:

$\sqrt{\Delta}=\sqrt{3920}=\sqrt{16*245}=\sqrt{16}*\sqrt{245}=4\sqrt{245}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-4\sqrt{245}}{2*9.8}=\frac{0-4\sqrt{245}}{19.6}
=-\frac{4\sqrt{245}}{19.6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+4\sqrt{245}}{2*9.8}=\frac{0+4\sqrt{245}}{19.6}
=\frac{4\sqrt{245}}{19.6}
$