The length of a rectangle is shown below:
if the area of the rectangle to be drawn is 20 square units, where should points c and d be located, if they lie vertically below the line that connects b and a, to make this rectangle?

Sorry if I get this wrong but if your trying to make a rectangle wouldn't it bc (-3,1) and (1,1)?

from the figure we get,

the x axis shows   the months and,

the y-axis shows the number of satisfied customer.

each line or each cell in upward direction (y-axis) shows 500.

the appropriate scale for the y - axis is: -

a = 2000 customers

b = 4000 customers

c = 6000 customers

d = 8000 customers

e = 10000 customers

f = 12000 customers

g = 14000 customers