7x^2-20=2500

Solution for 7x^2-20=2500 equation:

7x^2-20=2500

We move all terms to the left:

7x^2-20-(2500)=0

We add all the numbers together, and all the variables

7x^2-2520=0

a = 7; b = 0; c = -2520;
Δ = b2-4ac
Δ = 02-4·7·(-2520)
Δ = 70560
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:

$\sqrt{\Delta}=\sqrt{70560}=\sqrt{7056*10}=\sqrt{7056}*\sqrt{10}=84\sqrt{10}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-84\sqrt{10}}{2*7}=\frac{0-84\sqrt{10}}{14}
=-\frac{84\sqrt{10}}{14}
=-6\sqrt{10}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+84\sqrt{10}}{2*7}=\frac{0+84\sqrt{10}}{14}
=\frac{84\sqrt{10}}{14}
=6\sqrt{10}
$