Solve for a
a=11
a=-11
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2a^{2}=\left(11\sqrt{2}\right)^{2}
Combine a^{2} and a^{2} to get 2a^{2}.
2a^{2}=11^{2}\left(\sqrt{2}\right)^{2}
Expand \left(11\sqrt{2}\right)^{2}.
2a^{2}=121\left(\sqrt{2}\right)^{2}
Calculate 11 to the power of 2 and get 121.
2a^{2}=121\times 2
The square of \sqrt{2} is 2.
2a^{2}=242
Multiply 121 and 2 to get 242.
2a^{2}-242=0
Subtract 242 from both sides.
a^{2}-121=0
Divide both sides by 2.
\left(a-11\right)\left(a+11\right)=0
Consider a^{2}-121. Rewrite a^{2}-121 as a^{2}-11^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
a=11 a=-11
To find equation solutions, solve a-11=0 and a+11=0.
2a^{2}=\left(11\sqrt{2}\right)^{2}
Combine a^{2} and a^{2} to get 2a^{2}.
2a^{2}=11^{2}\left(\sqrt{2}\right)^{2}
Expand \left(11\sqrt{2}\right)^{2}.
2a^{2}=121\left(\sqrt{2}\right)^{2}
Calculate 11 to the power of 2 and get 121.
2a^{2}=121\times 2
The square of \sqrt{2} is 2.
2a^{2}=242
Multiply 121 and 2 to get 242.
a^{2}=\frac{242}{2}
Divide both sides by 2.
a^{2}=121
Divide 242 by 2 to get 121.
a=11 a=-11
Take the square root of both sides of the equation.
2a^{2}=\left(11\sqrt{2}\right)^{2}
Combine a^{2} and a^{2} to get 2a^{2}.
2a^{2}=11^{2}\left(\sqrt{2}\right)^{2}
Expand \left(11\sqrt{2}\right)^{2}.
2a^{2}=121\left(\sqrt{2}\right)^{2}
Calculate 11 to the power of 2 and get 121.
2a^{2}=121\times 2
The square of \sqrt{2} is 2.
2a^{2}=242
Multiply 121 and 2 to get 242.
2a^{2}-242=0
Subtract 242 from both sides.
a=\frac{0±\sqrt{0^{2}-4\times 2\left(-242\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 0 for b, and -242 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
a=\frac{0±\sqrt{-4\times 2\left(-242\right)}}{2\times 2}
Square 0.
a=\frac{0±\sqrt{-8\left(-242\right)}}{2\times 2}
Multiply -4 times 2.
a=\frac{0±\sqrt{1936}}{2\times 2}
Multiply -8 times -242.
a=\frac{0±44}{2\times 2}
Take the square root of 1936.
a=\frac{0±44}{4}
Multiply 2 times 2.
a=11
Now solve the equation a=\frac{0±44}{4} when ± is plus. Divide 44 by 4.
a=-11
Now solve the equation a=\frac{0±44}{4} when ± is minus. Divide -44 by 4.
a=11 a=-11
The equation is now solved.
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