Find BC. A. 22.5 in B. 29 in C. 30 in D. 28 in

Answer: B. 29 mi (which you typed 29 in)
Step-by-step explanation:
Use law of cosine to solve: a²=b²+c²-2bc·cosA (the corresponding angle)
a²=19²+12²-2×19×12×cos (138)
a²=361+144-456cos(138)
a²=505-456cos(138)
a²=843.874 (rounded)
a=29 mi