Answer:
B
Step-by-step explanation:
You are given two sides and the included angle, so you need to use the law of cosines.
c² = a² + b² - 2ab cos C
c² = 12² + 13² - 2(12)(13)cos 134°
c² = 313 - 312(-0.6947)
c² = 529.733
c = 23.016
Now use the law of sines.
c/sin C = a/sin A
23.016/sin 134° = 12/sin A
sin A = 12 × sin 134° / 23.016
sin A = 0.37504
A = 22.03°
B = 180° - 134° - 22.03°
B = 23.97°
m<A = 22°; m<B = 24°; c = 23 km
Answer: B
