Shapes hiding in a tangle
Which one of these four shapes is hidden in the tangle of lines?
Work this one through before trying your own. The tangle holds 15 lines. Exactly one of the four shapes below can be traced along them.
Geometry figure: polygon. Vertices: . Sides: . Segments: (55, 97) to (37, 61); (105, 123) to (139, 106); (37, 160) to (18, 182); (75, 138) to (57, 101); (101, 125) to (75, 138); (28, 49) to (57, 90); (57, 101) to (101, 125); (127, 176) to (138, 158); (329, 75) to (329, 11); (48, 93) to (25, 134); (77, 142) to (95, 178); (71, 140) to (37, 157); (234, 61) to (193, 38); (54, 247) to (61, 209); (33, 103) to (46, 114). Angles: . There are 4 pictured outline options.
Answer: A
How you get there
Shape A is the only one of the four that can be traced out of the tangle, because a hidden shape keeps every side length and every corner angle however it is turned. Lock onto its longest side, about 50 units, find a line that length in the tangle, then check that the next side turns the way the tile says it should. The other three tiles have a side of the wrong length or a corner in the wrong place, so no matter where you start they run out of lines to follow. The lines that cross the shape or carry on past its corners are camouflage and belong to nothing.
Why the other answers tempt
A shape that is nearly right is wrong: check every side length, not just the number of corners.
If they are stuck, say this
Find the longest side of one tile, hunt the tangle for a line that long, then check whether the next side turns the way the tile says it should.
Now do it live in Shape Spotlight
