MBA.com questions on perimeter of a Triangle

[shantascherla]

If a triangle has two sides 2 & 5. what could be the perimeter

1 9
2 15
3 19

Solution is none

How does one approach when such questions when the triangle type is not defined at all..?

[jnelson0612]

Hi shanta,
Is this question from the GMAT prep test provided to you by mba.com?

[shantascherla]

Yes jamie it is part of the first test

[tim]

this is a triangle inequality problem. what you want to do is take the potential perimeters and use each to figure out what the third side is. once you know all three sides, you can only form a valid triangle if the two shorter sides add up to more than the third side. you don't need to know anything else about what the triangle is supposed to look like..

[sthitaprajnadas]

As per triangle inequality theorem sum of length any two sides of a triangle should always be more than the length of the third side and dfifference between the lenghts of two sides should always be less than the third side.

going by this: Here the length of third side 3< L3 <7
hence perimeter 3+7 < P < 7+7 lies between 10 and 14 hence none fits the bill.

Sthita

[tim]

exactly..