0=-4.9x^2+10x+1200

Solution for 0=-4.9x^2+10x+1200 equation:

0=-4.9x^2+10x+1200

We move all terms to the left:

0-(-4.9x^2+10x+1200)=0

We add all the numbers together, and all the variables

-(-4.9x^2+10x+1200)=0

We get rid of parentheses

4.9x^2-10x-1200=0

a = 4.9; b = -10; c = -1200;
Δ = b2-4ac
Δ = -102-4·4.9·(-1200)
Δ = 23620
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:

$\sqrt{\Delta}=\sqrt{23620}=\sqrt{4*5905}=\sqrt{4}*\sqrt{5905}=2\sqrt{5905}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-10)-2\sqrt{5905}}{2*4.9}=\frac{10-2\sqrt{5905}}{9.8}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-10)+2\sqrt{5905}}{2*4.9}=\frac{10+2\sqrt{5905}}{9.8}
$