Answer: 24
Step-by-step explanation: alright since AC = x+ 19, x+19 is equal to 2x+9+x. This means :
x+19 = 3x+9
subtract 19 from both sides:
x = 3x-10
now subtract 3x on both sides:
-2x = -10
Multiply by -1 on both sides:
2x = 10
x=5
Now we just add 19 to 5 to get 24