Lenny Conundrum 218

[AySz88]

The forum outage caused a skip of LC 217, but the full solution is here: http://www.neopets.com/games/conundrum_ ... ?round=217

LC 218:

If you assemble these puzzle pieces correctly, you should be able to figure out what to do next.

Hint: The Conundrum Lenny has sure been keeping up with his dailies...the answer to the question is trivial if you did too.

500th post!

[Katherine]

Puzzles!Yey!

[Jerch]

For Round 217, while it seems obvious, I simply can't think of how to prove that '16' and 'a' is a straight line, and not just two lines joined at a point...
(i.e. that an extension of the red line passes through the centre.)

TNT's solution skipped that part, and simply went on to assume that it does.

[AySz88]

Because if it wasn't a straight line, the two 24-cm lines would need to be unequal. (Not exactly a fleshed-out proof, but best I can come up with at this hour... )

[Jerch]

Hmm....feel free to ignore the question in my previous post. [Sorry]
Just worked it out myself after really looking at the problem , there's no need to prove by contradiction.

All that's needed, is to utilize the pair of congruent triangles, and the fact that the two longer lines are parallel...
though really, TNT should've included that in their proof. Their proof simply didn't make any sense to me, the first time I've looked at it....