Re: The length of one side of a triangle is 12. The length of an
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17 Mar 2019, 18:57
This one is testing the triangle inequality theorem, which states that the sum of any two sides must be greater than the length of the third side.
The sum of our lengths so far is 30. Our answer, choices, then, posit a third side with a length of:
A. 0
B. 6
C. 14
D. 18
E. 30
Clearly the third side can't be 0, so A is out. B doesn't work either, because 12 + 6 = 18, meaning that the sum of two sides is not greater than the third side.
C and D work just fine.
E, however, is also out. Again, 12 + 18 = 30, which means that the sum of two sides is not greater than the third.