7x^2+10x-100=0

Solution for 7x^2+10x-100=0 equation:

7x^2+10x-100=0

a = 7; b = 10; c = -100;
Δ = b2-4ac
Δ = 102-4·7·(-100)
Δ = 2900
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:

$\sqrt{\Delta}=\sqrt{2900}=\sqrt{100*29}=\sqrt{100}*\sqrt{29}=10\sqrt{29}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(10)-10\sqrt{29}}{2*7}=\frac{-10-10\sqrt{29}}{14}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(10)+10\sqrt{29}}{2*7}=\frac{-10+10\sqrt{29}}{14}
$