Answer:
x=10
Step-by-step explanation:
BD/CD=AB/AC
x+4/2x+1=8/12
12(x+4)=8(2x+1)
12x+48=16x+8
12x+48-8=16x+8-8
40=4x
40/4=4x/4
10=x
Hope this helps! ;)
