I do not get still problem 1 and 3.  For problem one how do you know that the shape equals 360.  For problem three i still dont understand how you got 17

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Well, for 3, he got 17 b/c 8-15-17 is a Pythagorean triple. this is true b/c 8 sq. + 15 sq. = 17 sq. I can't remember the exact numbers for each squared, but check it on a calculator. It should be correct.