Question

Use the image to answer the question.

A triangle ABC with side AB marked as c, side BC as a which is equal to 10 inches, and CA as b which is equal to 15 inches. Angle ACB is labeled 40 degrees and angle ABC is labeled 85 degrees.

Using the Law of Sines, which ratio can help you correctly find the value of angle A
?

(1 point)

sin A10=sin 85°15


sin A15=sin 85°40


sin A15=sin 85°10


sin A15=sin 40°10

Answer 1

Use a/sin A = b/sin B. Here a = 10, b = 15, B = 85° so

10 / sin A = 15 / sin 85°, i.e. sin A / 10 = sin 85° / 15.

(Choice 1.)