Answer: 8.7 miles
Explanation
We have a right triangle with one leg as 5 miles and hypotenuse as 10 miles.
Use the Pythagorean Theorem and get
\(5^2+x^2=10^2\), where x is the missing leg.
\(25+x^2=100, x^2=75\).
Take the square root of both sides. (You need a calculator for this.)
\(\sqrt{75}=8.6603\), or to the nearest tenth, just \(8.7\) miles.
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