The equation would be
m = 7 * w
Since we know w = 5
7*5 = 35.
Edit: I just realized this question is more complex than I realized.
The equation would be
m = 7*w
To graph that put "Weeks" on the Y-Axis (Up and down line) and place "Money earned in total" on the X-axis (side to side line)
Now number the Y-Axis 1, 2, 3, 4, etc. starting at the bottom and going up,
now number the X-Axis, 7, 14, 21, etc. adding on 7 each time.
To answer "How much money does he make if he brings in the mail for 5 weeks" draw a line starting at the bottom left corner to where the 5 Weeks and 35$ Earned lines connect.