Question

Which proportion could be used to find the length of side b?

Answer 1

Answer:

D   sin 85         sin 31

    ---------- =     ----------

      b                  9.3

Step-by-step explanation:

We can use the law of sins

sin B        sin A         sin C

---------- = ----------- = ----------

b                   a            c

We do not know angle C, but we can calculate it

The angles of a triangle add to 180

A + B + C = 180

64+ 85 + C = 180

149 + C = 180

C = 180-149

C =31

sin B         sin C

---------- = ----------

b                  c

We know B =  85, C = 31, b = unknown and c = 9.3

sin 85         sin 31

---------- = ----------

b                  9.3