0=-2x^2+98x-720

Solution for 0=-2x^2+98x-720 equation:

0=-2x^2+98x-720

We move all terms to the left:

0-(-2x^2+98x-720)=0

We add all the numbers together, and all the variables

-(-2x^2+98x-720)=0

We get rid of parentheses

2x^2-98x+720=0

a = 2; b = -98; c = +720;
Δ = b2-4ac
Δ = -982-4·2·720
Δ = 3844
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{3844}=62$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-98)-62}{2*2}=\frac{36}{4}
=9
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-98)+62}{2*2}=\frac{160}{4}
=40
$