Question

Given: ΔABC. If ∠B = 35°, a = 4.5 cm, and b = 6.0 cm, what is the measurement of ∠A to the nearest tenth of a degree?

A) 21.5°
B) 23.2°
C) 25.5°
D) 30.7°

Answer 1

we know that

the law of sines established
a/sin A=b/sin B--------sin A=[a*sin B]/b
a=4.5 cm
b=6 cm
B=35°
so
sin A=[4.5*sin 35°]/6-----> sin A=0.43018
A=arc sin(0.43018)-------> A=25.5°

the answer is the option
C) 25.5°