Answer:
BC = 4.7
Explanation:
From the question given above, the following data were:
Angle A = 21 °
Hypothenus = AC = 13
Opposite = BC =?
The length of BC can be obtained by using sine ratio as illustrated below:
Sine A = Opposite /Hypothenus
Sine 21 = BC / 13
0.3584 = BC / 13
Cross multiply
BC = 0.3584 × 13
BC = 4.7
Thus, the length of BC is 4.7