x2+20x2-200=0

Solution for x2+20x2-200=0 equation:

x2+20x^2-200=0

We add all the numbers together, and all the variables

21x^2-200=0

a = 21; b = 0; c = -200;
Δ = b2-4ac
Δ = 02-4·21·(-200)
Δ = 16800
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:

$\sqrt{\Delta}=\sqrt{16800}=\sqrt{400*42}=\sqrt{400}*\sqrt{42}=20\sqrt{42}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-20\sqrt{42}}{2*21}=\frac{0-20\sqrt{42}}{42}
=-\frac{20\sqrt{42}}{42}
=-\frac{10\sqrt{42}}{21}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+20\sqrt{42}}{2*21}=\frac{0+20\sqrt{42}}{42}
=\frac{20\sqrt{42}}{42}
=\frac{10\sqrt{42}}{21}
$