Answer: 15 feet (choice B)
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Work Shown:
[tex]a^2 + b^2 = c^2 \ \ \text{ ... pythagorean theorem}\\\\12^2 + 9^2 = c^2\\\\144 + 81 = c^2\\\\225 = c^2\\\\c^2 = 225\\\\c = \sqrt{225}\\\\c = 15\\\\[/tex]
