Quadrilateral Lengths

[vampirewitchreine]

Try to draw a quadrilateral with sides of the given lengths. Is it possible? Explain why or why not.

A. 2 in., 3 in., 4 in., and 9 in.
(Others in this problem- B. 2 in., 3 in., 4 in., and 12 in.; C. 2 in., 3 in., 4 in., and 8 in)



Should I set this up like triangle inequality or should I do something else? I did cut out strips of paper to attempt this, but I'm not sure if I've been doing this properly. I know that the smaller lengths all add up to equal the longer side for A. B the smaller lengths are shorter than the longest and in C the smaller lengths are longer that the biggest side.

 

[soroban]

Hello, vampirewitchreine!

Try to draw a quadrilateral with sides of the given lengths.
. . Is it possible? Explain why or why not.
(All measurements are in inches.)

(A) 2, 3, 4, 9

(B) 2, 3, 4, 12

(C) 2, 3, 4, 8

Should I set this up like triangle inequality or should I do something else?
. . Yes, there IS an inequality that applies here.

I did cut out strips of paper to attempt this, but I'm not sure if I've been doing this properly.
I know that the smaller lengths all add up to equal the longer side for (A),
(B) the smaller lengths are shorter than the longest,
and in (C) the smaller lengths are longer that the biggest side.
Now that you've played with strips of paper, can you see that you could have drawn conclusions from just the numbers?
By the way, what ARE your conclusions?

I hope you see that neither (A) nor (B) can form a quadrilateral.
. . If you don't, you need more help than we can offer.