Evaluate
-28
Factor
-28
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\frac{-7\times 2\sqrt{2}}{\frac{1}{\sqrt{2}}}
Factor 8=2^{2}\times 2. Rewrite the square root of the product \sqrt{2^{2}\times 2} as the product of square roots \sqrt{2^{2}}\sqrt{2}. Take the square root of 2^{2}.
\frac{-14\sqrt{2}}{\frac{1}{\sqrt{2}}}
Multiply -7 and 2 to get -14.
\frac{-14\sqrt{2}}{\frac{\sqrt{2}}{\left(\sqrt{2}\right)^{2}}}
Rationalize the denominator of \frac{1}{\sqrt{2}} by multiplying numerator and denominator by \sqrt{2}.
\frac{-14\sqrt{2}}{\frac{\sqrt{2}}{2}}
The square of \sqrt{2} is 2.
\frac{-14\sqrt{2}\times 2}{\sqrt{2}}
Divide -14\sqrt{2} by \frac{\sqrt{2}}{2} by multiplying -14\sqrt{2} by the reciprocal of \frac{\sqrt{2}}{2}.
\frac{-14\sqrt{2}\times 2\sqrt{2}}{\left(\sqrt{2}\right)^{2}}
Rationalize the denominator of \frac{-14\sqrt{2}\times 2}{\sqrt{2}} by multiplying numerator and denominator by \sqrt{2}.
\frac{-14\sqrt{2}\times 2\sqrt{2}}{2}
The square of \sqrt{2} is 2.
\frac{-28\sqrt{2}\sqrt{2}}{2}
Multiply -14 and 2 to get -28.
\frac{-28\times 2}{2}
Multiply \sqrt{2} and \sqrt{2} to get 2.
\frac{-56}{2}
Multiply -28 and 2 to get -56.
-28
Divide -56 by 2 to get -28.
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