Answer:
A. 7.5 cm
Step-by-step explanation:
3/4 = (x + 3)/(2x + 1)
3(2x + 1) = 4(x + 3)
6x + 3 = 4x + 12
2x = 9
x = 4.5
BC = x + 3
= 4.5 + 3
= 7.5 cm