Problem Solving

If two sides of a tringle have lenghts 2 and 5,which of the foll could be the perimeter??

9
15
19

none
1 only
2 only
2 and 3 only
1,2 and 3

I - perimeter 9 would mean 5+2+x=9 -> x=2, impossible, the sum of every two sides of a triangle must be greater than the third side. 2+2=4 < 5.
II - perimeter 15 would mean x=8 5+2=7 < 8 impossible

III - perimeter 19 x= 12 5+2=7 < 12 impossible
Answer is A

The answer should be 1 only - 9

Reason :

perimeter 9 -> 5+2+x=9 -> x=2
Isoceles triangle satisfies the condition.

tanyajoseph wrote:The answer should be 1 only - 9

Reason :

perimeter 9 -> 5+2+x=9 -> x=2
Isoceles triangle satisfies the condition.

A triangle with sides 5,2,2 cannot be drawn , bcoz the side of every triangle should meet a very important rule .. the sum of any 2 sides should be greater than the 3rd side( this is the same one that agps mentioned in his post) .. so a triangle with sides 5,2,2 cannot be drawn bcoz 2+2< 5 ..

.. I agree with agps' answer ..