Hi, you've asked an incomplete question. I attached the missing caption that completes the question.
Explanation:
By looking closely at the caption we notice there are measuring coordinates along the margin of the caption. To find the middle of the chairs, take note of the total coordinate distances between points C and D;
- For the vertical axis, the distance is 4
- For the horizontal axis, the distance is 2
Substracting both differences in distances we get 2 (4-2) so at point (10, 7) we find the middle or halfway between the chairs at points C and D.
