Answer:
BC=2
Step-by-step explanation:
Consider right triangle ABC with right angle C and angle A of the measure of 30°. In this triangle, AB=4.
Theorem: The leg opposite to the 30° angle is half of the hypotenuse.
Note that AB=4 is the hypotenuse, angle A has the meausre of 30°, then the leg BC is half of AB:
[tex]BC=\dfrac{1}{2}AB=\dfrac{1}{2}\cdot 4=2.[/tex]
