Quick math, please help! What is the length of side BC in the triangle? Thank you!

Answer:
I got 24 for the answer!
Step-by-step explanation:
x+8=2x-1
solve for x, and you will get x=9
then you will plug this into bc, 3x-3, and that will be 3(9)-3, and you will get 24! Hope this is right!