Given the following triangle, if a = 12 and ∠b = 48°, find b to the nearest whole number.

In the figure, the triangle ABC is a right triangle, a is the adjacent leg to the angle B, and b is the opposite side to the same angle.

So, you can use the tangent ratio which relates the angle, the opposite leg and the adjacent leg:

tangent (angle B) = b / a => b = a * tan(B)

=> b = 12 * tan(48°) = 13.33≈ 13

13

21/2 or 5/2