X2+55x-300=0

Solution for X2+55x-300=0 equation:

X2+55X-300=0

We add all the numbers together, and all the variables

X^2+55X-300=0

a = 1; b = 55; c = -300;
Δ = b2-4ac
Δ = 552-4·1·(-300)
Δ = 4225
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{4225}=65$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(55)-65}{2*1}=\frac{-120}{2}
=-60
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(55)+65}{2*1}=\frac{10}{2}
=5
$