A triangle has side lengths of 18 & 13. Which of the following could not be a measure of the third side?
1) 30
2) 5
3) 22
4) 4

Question

A triangle has side lengths of 18 & 13. Which of the following could not be a measure of the third side?
	1)	30
	2)	5
	3)	22
	4)	4

inkyvoyd · Answer

In a triangle, any two of the three sides must have a combined total length longer than that of the third.

anonymous · Answer

all of those are valid values execept for 4 and 5.  so the answer is 2 and 4.

this is because in the sum of the two smaller sides MUST be larger than the third side.

IE if you have sides 13-18-22 then 13+18 > 22
etcetc

anonymous · Answer

i cant pick Both

parthkohli · Answer

Yeah, both. I don't know about that.

anonymous · Answer

Pick 4 then. However both is the right answer.

callisto · Answer

Now, set up the inequalities to see what you'd get. Let x be the length of the 3rd side
(I) 18+13> x  => x<31
(II) 18+x > 13 => x> 13-18 => x>-5
(III) x+13> 18 => x>5
Hmm.. two answers :S

anonymous · Answer

lost .

anonymous · Answer

about the answer? or how to approach the answer?

anonymous · Answer

are*

inkyvoyd · Answer

4 is not valid

callisto · Answer

Neither 5...

inkyvoyd · Answer

I read teh problem wrong

anonymous · Answer

3. ?

callisto · Answer

Option 3 is correct. It is smaller than 31 but greater than 5.