Question

In △ABC, m∠A=16°, m∠B=49°, and a=4. Find c to the nearest tenth.

Answer 1

c=13.2 units

Explanation:

step 1

Find the measure of angle C

Remember that the sum of the internal angles of a triangle must be equal to 180 degrees

so

A+B+C=180°

substitute the given values

16°+49°+C=180°

65°+C=180°

C=180°-65°=115°

step 2

Find the measure of c

Applying the law of sines

c/sin(C)=a/sin(A)

substitute the given values and solve for c

c/sin(115°)=4/sin(16°)

c=4(sin(115°))/sin(16°)

c=13.2 units