7x^2=261

Solution for 7x^2=261 equation:

7x^2=261

We move all terms to the left:

7x^2-(261)=0

a = 7; b = 0; c = -261;
Δ = b2-4ac
Δ = 02-4·7·(-261)
Δ = 7308
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:

$\sqrt{\Delta}=\sqrt{7308}=\sqrt{36*203}=\sqrt{36}*\sqrt{203}=6\sqrt{203}$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-6\sqrt{203}}{2*7}=\frac{0-6\sqrt{203}}{14}
=-\frac{6\sqrt{203}}{14}
=-\frac{3\sqrt{203}}{7}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+6\sqrt{203}}{2*7}=\frac{0+6\sqrt{203}}{14}
=\frac{6\sqrt{203}}{14}
=\frac{3\sqrt{203}}{7}
$