HELP !! Statement

Reason

1. Draw a line through B that is perpendicular to and

label the point of intersection with as D.

construction

2. In ΔABD, BD = c sin A.

definition of sine in a right triangle

3. In ΔCBD, BD = a sin C.

definition of sine in a right triangle

4. c sin A = a sin C

Substitution Property of Equality

5. dividing throughout by sin A sin C

6. Draw a line through A that is perpendicular to and

label the point of intersection with as E.

construction

7. In ΔBAE, AE = c sin B.

definition of sine in a right triangle

8. In ΔCAE, AE = b sin C.

definition of sine in a right triangle

9. c sin B = b sin C

Substitution Property of Equality

10.

dividing throughout by sin B sin C

11.

Transitive Property of Equality

What is the missing statement in step 10 of the proof?

Given: ΔABC

with AB = c, BC = a, AC = b

Prove: a/sin a = b/ sin b = c/ sin c