9*8x = 72
9* 10 = 90
so far, 72x + 90 + 9(9-x)
9 * 9 = 81
9 * -x = -9x
now, we have: 72x + 90 + 81 -9x
Now we can simplify by combining like terms
72x - 9x = 63x
90 + 81 = 171
63x + 171 is our answer
The answer is B.
Hope I helped!
Let me know if you need anything else!
~ Zoe