Problema Solution

Part A: Sam rented a boat at $225 for 2 days. If he rents the same boat for 5 days, he has to pay a total rent of $480. Write an equation in the standard

form to represent the total rent (y) that Sam has to pay for renting the boat for x days. Part B: Write the equation obtained in Part A using function notation. Part C: Describe the steps to graph the equation obtained above on the coordinate axes. Mention the labels on the axes and the intervals.

Answer provided by our tutors

Part A:

The Standard Form equation of a line has the following formula:

Ax+By=C, where A, B, and C are integers, and A is non-negative.

We will assume that when renting a boat Sam paid fixed cost and rental charge per day.

y = the total rent

x = the number of days

Sam rented a boat at $225 for 2 days would mean:

y = 225 when x = 2 or if we plug into Ax+By=C:

2A + 225B = C since A is non-negative we divide both sides by A

2 + (B/A)225 = C/A

He rents the same boat for 5 days, he has to pay a total rent of $480 means:

y = 480 when x = 5 days

5A + 480B = C since A is non-negative we divide both sides by A

5 + (B/A)480 = C/A

Now we have:

2 + (B/A)225 = C/A

5 + (B/A)480 = C/A

Lets denote s = B/A  and t = C/A. Now we can write the following system of equations:

2 + 225s = t

5 + 480s = t

........

click here to see the system of equations solved for s and t

........

s = -1/85

t = -11/17 = -55/85

Now we can go back to:

B/A = -1/85 and C/A = -55/85

A = 85, B = -1, C = -55

The standard equation is:

85x - y = -55

Part B:

Using the equation 85x - y = -55 we solve for y

.......

click here to see the equation solved for y

........

y = 85x + 55

or in function notion y = f(x)

f(x) = 85x + 55

Part C:

The graph of y = 85x + 55 is: