11x^2=x^2+9

Solution for 11x^2=x^2+9 equation:

11x^2=x^2+9

We move all terms to the left:

11x^2-(x^2+9)=0

We get rid of parentheses

11x^2-x^2-9=0

We add all the numbers together, and all the variables

10x^2-9=0

a = 10; b = 0; c = -9;
Δ = b2-4ac
Δ = 02-4·10·(-9)
Δ = 360
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:

$\sqrt{\Delta}=\sqrt{360}=\sqrt{36*10}=\sqrt{36}*\sqrt{10}=6\sqrt{10}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-6\sqrt{10}}{2*10}=\frac{0-6\sqrt{10}}{20}
=-\frac{6\sqrt{10}}{20}
=-\frac{3\sqrt{10}}{10}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+6\sqrt{10}}{2*10}=\frac{0+6\sqrt{10}}{20}
=\frac{6\sqrt{10}}{20}
=\frac{3\sqrt{10}}{10}
$