14x^2+1400x-12600=0

Solution for 14x^2+1400x-12600=0 equation:

14x^2+1400x-12600=0

a = 14; b = 1400; c = -12600;
Δ = b2-4ac
Δ = 14002-4·14·(-12600)
Δ = 2665600
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:

$\sqrt{\Delta}=\sqrt{2665600}=\sqrt{78400*34}=\sqrt{78400}*\sqrt{34}=280\sqrt{34}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(1400)-280\sqrt{34}}{2*14}=\frac{-1400-280\sqrt{34}}{28}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(1400)+280\sqrt{34}}{2*14}=\frac{-1400+280\sqrt{34}}{28}
$