Question

In a triangle ABC, A = 30°, a = 2 and c = 4 then C equals to
A) 60°
B) 90°
C) 75°
D) 90°​

Answer 1

Answer:

angle C = 90°

Step-by-step explanation:

In a triangle ABC, A + B + C = 180°

given, A = 30° => 30° + B + C = 180°

=> B + C = 180° - 30° = 150°

given, a = 2 and c = 4

=> BC = 2 and AB = 4

BC / AB = 2 / 4 = 1 / 2

the angle opposite to side BC is A = 30°

so, if you consider the given triangle ABC is right angled triangle, sin 30° = 1/2 = BC/AB

=> AB is hypotenuse

and the angle opposite to hypotenuse is right angle

.•. angle C = 90°