Question

Solve a triangle when A= 40° C = 70°, and a = 20.

a. B = 70°; B = 18.1;c = 18.1
b. B = 40°; b = 29.2; C = 29.2
d.
B = 70°, 5 = 29.2; C = 29.2
B = 40°; b = 18.1;c = 18.1
Please select the best answer from the choices provided

Answer 1

The correct answer is C. B = 70, b = 29.2, c = 29.2

Explanation:

This was the correct answer on edge,

The numbering for this question should of been A, B, C, D, instead of a, b, B, B

Answer 2

B = 70°, b = 29.2; c = 29.2

Explanation:

sum of angles in a triangle is 180

40+70 +X = 180

X is the last angle

110+x=180

x= 180-110 =70

A= 40°

B= 70°

C= 70°

the triangle is Isosceles triangle meaning two sides are equal , angle B = angle C

side b= side c

using Sine Rule

a/sin A = b/Sin B

20/sin 40 = b/sin 70

sin 40 = 0.6427

sin 70 = 0.93969

20/0.6427 = b/ 0.93969

cross multiply

20 x 0.93969 = 0.6427b

18.7938=0.6427b

b = 18.7938/0.6427

b = 29.2419≈29.2

side b= side c = 29.2

B= 70°. side b = 29.2, side c = 29.2