A triangle has two sides that measure 12 meters and 3 meters. Which could be the measure of the third side?

A. 17 m
B. 15 m
C. 10 m
D. 9 m

Question

A triangle has two sides that measure 12 meters and 3 meters. Which could be the measure of the third side?

	A.	17 m
	B.	15 m
	C.	10 m
	D.	9 m

anonymous · Answer

The 3rd side of a triangle with a side of 12 and one of 3 would have to be >12-3 and <12+3.

Do you see why that is true?

anonymous · Answer

Answers A, B, and D don't make a triangle.  One of the specifications for a triangle is that the sum of the other two sides must exceed the longest side.  None of these combinations work.  Since 10+3>12, answer C will work.