Answer:
⇒Store i charges $4 for one-time membership fee and a fee of $1.50 per rented DVD
⇒Store ii charges $5 for one-time membership fee and a fee of $2 per rented DVD
⇒ Renting a DVD in shop {i} is cheaper than in shop {ii}
Step-by-step explanation:
In the first store, the equation for cost can be calculated as;
Find slope using the data set
Number of DVDs rented Cost {$}
1 5.50
2 7.0
3 8.50
m= Δy/Δx
m= 8.50 - 5.50 / 3-1
m= 3/2 = 1.5
Write the equation
m= Δy/Δx
1.5 = y-7/ x-2
1.5 { x-2 } = y-7
1.5 x - 3.0 = y-7
1.5x -3.0 + 7 = y
1.5 x + 4= y
C= 4 + 1.5 d ------where d is the number of DVDs rented
Comparing the two equations that model the cost of renting DVDs
i) C= 4 + 1.5d
ii) C=5 + 2d
⇒Store i charges $4 for one-time membership fee and a fee of $1.50 per rented DVD
⇒Store ii charges $5 for one-time membership fee and a fee of $2 per rented DVD
For example 2 DVDs are rented in both store, you can find the store which is cheaper as;
i) C= 4 + 1.5d = 4+ 1.5*2 = 4 + 3 = $7
ii) C=5 + 2d = 5 + 2 * 2 = 5 + 4 = $9
⇒ Renting a DVD in shop {i} is cheaper than in shop {ii}