-1000=-4.9(x)^2

Solution for -1000=-4.9(x)^2 equation:

-1000=-4.9(x)^2

We move all terms to the left:

-1000-(-4.9(x)^2)=0

We get rid of parentheses

4.9x^2-1000=0

a = 4.9; b = 0; c = -1000;
Δ = b2-4ac
Δ = 02-4·4.9·(-1000)
Δ = 19600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{19600}=140$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-140}{2*4.9}=\frac{-140}{9.8}
=-14+2.8/9.8
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+140}{2*4.9}=\frac{140}{9.8}
=14+2.8/9.8
$