Angle Explorer
Geometry · Class VI
Pick an angle from 0 to 360 and see its complement, supplement and reflex.
- Complement60
- Supplement150
- Reflex330
- Radians0.5236
Formulas in this lab
- Complement
- Supplement
- Reflex
- Radians
Frequently asked questions
▶What are complementary, supplementary and reflex angles?
Two angles are complementary if they add to 90 degrees and supplementary if they add to 180. The reflex angle of t is 360 - t, which is what is left after going around. So for t = 30, complement is 60, supplement is 150 and reflex is 330.
▶How do I use the angle explorer lab?
Slide t between 0 and 360 degrees. The lab shows 90 - t (complement), 180 - t (supplement) and 360 - t (reflex). Try t = 45 to see complement 45, supplement 135 and reflex 315.
▶How do angles show up around me?
The hands of a wall clock make changing angles all day. At 3 oclock the angle is 90 degrees, at 6 it is 180, and at 12 they overlap at 0. The lab lets you test other angle pairs you spot, like the slant of a kite or a ladder against a wall.
▶Complement vs supplement: how do I remember which is which?
C comes before S in the alphabet, and 90 comes before 180. So complement pairs with the smaller 90 and supplement pairs with the larger 180. The lab makes the difference visual: 90 - t shrinks fast, while 180 - t shrinks slower as you slide t.