DavidB4-bot
Spelling, grammar, and general cleanup
02:56
+28
Abcqwe
Re-categoized, expanded definition
22:56
+283
→top: clean up & uniformity
17:25
Iduan
that failed
01:06
-3
de-dead end
+17
Aziraphale
categorize
19:49
+26
SharonS
New page: '''Perpendicular lines''' are lines which intersect to form four <math>90^o</math> angles.
17:17
+90