In right triangle lmn, l and m are complementary angles and sin(l) is 19/20. what is cos(m)?
a.19/20
b.1/20
c.(square root of 39)/19
d.(square root of 39)/20

I believe the correct answer from the choices listed above is option A. In right triangle LMN, L and M are complementary angles and sin(L) is 19/20. Therefore, cosine of M would be 19/20 as well. It would be helpful if you draw a figure of the problem. Hope this answers the question.

Answer d; a supplementary angle = 180°, so if that angle = 150°, y would = 30°.