Answer:
<ABC = 54 degrees
Step-by-step explanation:
Taking the sum of angle on the straight line ABD as 180 degrees
3x+9 + 9x - 9 =180
12x = 180
x = 180/12
x = 15 degrees
Since <ABC = 3x+9 (vertically opposite angles)
<ABC = 3(15)+9
<ABC = 45+9
<ABC = 54 degrees
