0=-5x^2-155x+1330

Solution for 0=-5x^2-155x+1330 equation:

0=-5x^2-155x+1330

We move all terms to the left:

0-(-5x^2-155x+1330)=0

We add all the numbers together, and all the variables

-(-5x^2-155x+1330)=0

We get rid of parentheses

5x^2+155x-1330=0

a = 5; b = 155; c = -1330;
Δ = b2-4ac
Δ = 1552-4·5·(-1330)
Δ = 50625
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{50625}=225$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(155)-225}{2*5}=\frac{-380}{10}
=-38
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(155)+225}{2*5}=\frac{70}{10}
=7
$