Answer:
BC = 18.7
Explanation:
Here, we want to solve the triangle using the law of sines
According to the law, the ratio of the measure of the side of a triangle and the sine of the angle that faces the side is a constant for all sides of the triangle
Mathematically;
a/sin A = b/sin B = c/sin C
with reference to this particular triangle, we have it that;
20/sin 80 = BC/ sin 67
BC = 20 * sin 67/sin 80
BC = 18.7