Do congruent regular dodecagons (12-sided polygons) tessellate a plane?

12 is your heckling my recking

No because  a regular polygon is a two-dimensional shape with straight sides that all have equal length. A regular decagon is a 10-sided regular polygon. As it turns out, there are only three regular polygons that can be used to tessellate the plane: regular triangles, regular quadrilaterals, and regular hexagons.

B. two slopes of triangle abc are opposite reciprocals.
because if it is a right triangle, then the two sides/slopes make a 90 degree angle, which is also perpendicular, and perpendicular slopes have opposite reciprocals.