Use the Law of Sines to Solve Oblique Triangles Choose the o

Use the Law of Sines to Solve Oblique Triangles Choose the one alternative the best complete question. Solve the triangle. A) B = 45 degree, a = 8.11, c = 9.75 C) B = 50 degree, a = 8.11, c = 9.75

Solution

We know that the sum of three angles in a triangle is 180

=> Angle B = 180 - (80 + 55) = 45

By law of sines,

Sin A/a = Sin B/b = Sin C/c

sin 55/a = sin 45/7= sin 80/c

sin 55/a = sin 45/7

=> a = 8.11

Now,  sin 45/7= sin 80/c

=> c = 9.75

Hence, B = 45, a = 8.11 and c = 9.75