contestada

Solve the triangle.

B = 72°, b = 12, c = 8


A. Cannot be solved
B. C = 39.3°, A = 68.7°, a ≈ 16.5
C. C = 39.3°, A = 68.7°, a ≈ 11.8
D. C = 44.5°, A = 63.7°, a ≈ 11.8

Respuesta :

Solving the triangle.
B=72 , b =12, c = 8
Using the sine rule 
b/sin B= c/sin C
thus;  12/sin 72 = 8/sin C
          sin C = 8/12.618
                C= 39.3

The sum of angles in a triangle add up to 180°
Therefore, A +B+C=180
                            A = 180- (72+39.25)
                                = 68.7

Using the sine rule
a/sin A= b/sin b
therefore; a/sin 68.7 = 12/sin 72
                       a = (sin 68.7) ×12/sin 72
                          = (sin 68.7) ×12.618
                          = 11.756
                          ≈ 11.8

Otras preguntas