9514 1404 393
Answer:
x = 10
Step-by-step explanation:
The angle bisector divides the sides proportionally.
(2x +1)/12 = (x +4)/8
2(2x +1) = 3(x +4) . . . . . multiply by 24
4x +2 = 3x +12 . . . . . . . eliminate parentheses
x = 10 . . . . . . . . . . . . . . subtract 2+3x
