Question

assume that an angle B is an acute angle and sin(B-10degrees) =cos(11B-20degrees)

Answer 1

find angle B?

Answer 2

So if the sin is equal to the cosine the angles must be complementary.

Answer 3

sin 30 = cosine 60 and so on.

Answer 4

i got 6as the answer.. is that crrect?

Answer 5

Do you know what complementary means?

Answer 6

they equal the same, correct?

Answer 7

It means if you add them you get 90

Answer 8

oh, so i'm sorry, then would angle B=30?

Answer 9

\[B-10+11B-20=90\]
\[12B-30=90\]
\[12B=120\]
B=10

Answer 10

ah! got it. thank you~!!!!