I see this as a basic equation.
If she starts at point x, 8 feet, then goes down another 13, she is adding to the number of feet she traveled down.
So your answer would be 8+13=21
If this isn't what you needed, because I am not sure what math you are taking, let me know if I can help you more!
Answer:
it may be A log x ........
Step-by-step explanation:

Answer:
Step-by-step explanation:
(1,-4) is the answer reason why is you add the equations in order to solve for the first variable plug it in the equations in order to solve for the remaining variables