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a^{2}-\frac{25}{121}=0
Subtract \frac{25}{121} from both sides.
121a^{2}-25=0
Multiply both sides by 121.
\left(11a-5\right)\left(11a+5\right)=0
Consider 121a^{2}-25. Rewrite 121a^{2}-25 as \left(11a\right)^{2}-5^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
a=\frac{5}{11} a=-\frac{5}{11}
To find equation solutions, solve 11a-5=0 and 11a+5=0.
a=\frac{5}{11} a=-\frac{5}{11}
Take the square root of both sides of the equation.
a^{2}-\frac{25}{121}=0
Subtract \frac{25}{121} from both sides.
a=\frac{0±\sqrt{0^{2}-4\left(-\frac{25}{121}\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -\frac{25}{121} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
a=\frac{0±\sqrt{-4\left(-\frac{25}{121}\right)}}{2}
Square 0.
a=\frac{0±\sqrt{\frac{100}{121}}}{2}
Multiply -4 times -\frac{25}{121}.
a=\frac{0±\frac{10}{11}}{2}
Take the square root of \frac{100}{121}.
a=\frac{5}{11}
Now solve the equation a=\frac{0±\frac{10}{11}}{2} when ± is plus.
a=-\frac{5}{11}
Now solve the equation a=\frac{0±\frac{10}{11}}{2} when ± is minus.
a=\frac{5}{11} a=-\frac{5}{11}
The equation is now solved.