Answer:
(c-a, 0)
Step-by-step explanation:
The horizontal space between (c, b) and P is the same as the space between (a, b) and O.
Coordinates are written (x, y), where x is for horizontal space.
P is on the x-axis, making the y-coordinate 0.
(a+c, 0) would be to the right of the entire parallelogram.
(c, 0) would be directly below (c, b).
(a-c, 0) would be to the left of the entire parallelogram and in the other quadrant.
