Answer:
Option d. $68
Step-by-step explanation:
From the graph attached we will define the relation between Bill without the coupon and Bill with coupon.
Since graph is a linear function showing a straight line will be in the form of a straight line in the form of y = mx + c
where m = slope
c = y- intercept
Given line in the graph is passing through two points (2, 0) and (4, 2).
therefore m = (2-0)/(4-2) = 2/2 = 1
Now the line passing through (2, 0) and with slope 1 equation will be
0 = 1×2 + c ⇒ c = -2
Now the relation between bills with and without coupon can be represented by y = x - 2
Now we have to find the amount of bill without coupon if the bill with coupon was $66
Now with the help of the equation 66 = x - 2
x = 66 + 2 = $68