X2+28x-38=0

Solution for X2+28x-38=0 equation:

X2+28X-38=0

We add all the numbers together, and all the variables

X^2+28X-38=0

a = 1; b = 28; c = -38;
Δ = b2-4ac
Δ = 282-4·1·(-38)
Δ = 936
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:

$\sqrt{\Delta}=\sqrt{936}=\sqrt{36*26}=\sqrt{36}*\sqrt{26}=6\sqrt{26}$
$X_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(28)-6\sqrt{26}}{2*1}=\frac{-28-6\sqrt{26}}{2}
$
$X_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(28)+6\sqrt{26}}{2*1}=\frac{-28+6\sqrt{26}}{2}
$