X^2+30x-155=0

Solution for X^2+30x-155=0 equation:

X^2+30X-155=0

a = 1; b = 30; c = -155;
Δ = b2-4ac
Δ = 302-4·1·(-155)
Δ = 1520
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:

$\sqrt{\Delta}=\sqrt{1520}=\sqrt{16*95}=\sqrt{16}*\sqrt{95}=4\sqrt{95}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(30)-4\sqrt{95}}{2*1}=\frac{-30-4\sqrt{95}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(30)+4\sqrt{95}}{2*1}=\frac{-30+4\sqrt{95}}{2}
$