A video rental company offers a plan that includes a membership fee of $7 and charges $1 for every DVD borrowed. They also offer a second plan, that costs $29 per month for unlimited DVD rentals. If a customer borrows enough DVDs in a month, the two plans cost the same amount. How many DVDs is that? What is that total cost of either plan? If a customer rents ___ DVDs, each option costs $___.

If a customer rents 22 DVDs, each option costs $29

This only applies to one month.

Work Shown:

x = number of DVDs borrowed

y = total cost

Plan A has a cost of x+7 dollars since x represents the cost of renting the x DVDs plus the membership fee of $7. We can say y = x+7.

Plan B has a fixed cost of $29 per month, so y = 29. There is no x here to worry about as the cost is the same no matter how many DVDs you rent.

y = x+7 and y = 29 are dealing with the same y value. We can use substitution to solve for x

y = 29 ... start with second equation

x+7 = 29 replace y with x+7 (valid because y = x+7)

x+7-7 = 29-7 ... subtract 7 from both sides

x = 22

If the customer rents 22 DVDs, then plan A will charge y = x+7 = 22+7 = 29 dollars, which is the same as the flat rate cost plan B charges.

If the customer rents more than 22 DVDs per month, then its smarter to go with plan B (since plan A's cost will be larger). Otherwise, go for plan A.

In terms of a graph, you can graph both y = x+7 and y = 29 together on the same xy axis. The line y = x+7 goes through (0,7) and (1,8). The line y = 29 goes through (0,29) and (1,29). Both lines intersect at (22,29) to indicate that x = 22 and y = 29 pair up together.

x=-2

infinite number of lines, so there is an infinite number of equations.

step-by-step explanation:

there are an infinite number of line that passes through the point (-2,5)

x=-2   is one line that passes through the point

y = 5 is another line that passes through the point

(these two lines are perpendicular to each other).

since the number of   numbers are infinite and the slope is the ratio of two numbers,(change in y over change in x) we can have an infinite number of slopes.     our only condition is that it passes through the point (-2,5)

an advantage of the standard deviation is that it increases as the dispersion of the data increases. e. the interquartile range is preferred when the data are not skewed or no have outliers. an advantage of the standard deviation is that it uses all the observations in its computation.