You want to rent a scooter. sam’s scooters charges a $30 fee plus $8 per hour. rosie’s charges a $20 fee plus $10 per hour.

1. create a system of equations that represents this situation.

2. solve the system you created by substitution.

3. when does it make more sense to rent a scooter from rosie’s? how do you know?

4. when does it make more sense to rent a scooter from sam’s? how do you know?

5. is there ever a time where it wouldn’t matter which store to choose? explain.

6. if you were renting a scooter from both rosie’s and sam’s how much would you pay if you were planning on renting for 7 hours? show your work.

Let the charges per hour for the scooter = x (hours) and the total rent of the scooter = y (dollars)

Part 1: We have,

Sam's scooter charges $30 fee plus $8 per hour.

Thus, the scooter charges are,

Rosie's scooter charges $20 fee plus $10 per hour.

Thus, the scooter charges are,

Thus, the system of equations is, and

Part 2: On solving, we have,

..............(1)

..............(2)

From (1), we will substitute the value of y in (2), we get,

i.e. i.e. x= 5.

So, (1) implies i.e. i.e. y= 70.

Thus, for 5 hours, the rent of the scooter is $70 for both.

Part 3: It is sensible to rent from Rosie's means that the rent charges of Rosie are low.

That is, i.e.   i.e. x < 5.

So, whenever the number of hours are less than 5, it is sensible to rent the scooter at Rosie's.

Part 4: It is sensible to rent from Sam's means that the rent charges of Sam are low.

That is, i.e. i.e. x > 5.

So, whenever the number of hours are greater than 5, it is sensible to rent the scooter at Sam's.

Part 5: The time when it does not matter to choose a store will be when the prices of both the store are equal.

i.e. i.e. x = 5.

Thus, for 5 hours, the rent of the scooter is $70 for both and it does not matter which store to choose.

Part 6: If we are planning to rent for 7 hours, we have x= 7.

So, the rent from Rosie's is, i.e. i.e. y= $90

So, the rent from Sam's is, i.e. i.e. y= $86

So, the rent from Sam's and Rosie's for 7 hours are $86 and $90 respectively.

1.  C = 30+8h

C = 20 +10h

2.h = 5

C = 70

3.  When Rosies cost less, we want to rent from Rosies

When h is less than 5 hours

4.  When we want more then 5 hours ,we should rent from sams

5.  At exactly 5 hours the costs are the same, so we can rent from either store.

6.  Sams

C = 30+8(7) = 30 +56 = 86 dollars

Rosies

C = 20 +10(7) = 20+70 = 90 dollars

We want to rent from sams

Step-by-step explanation:

Sams

C = 30+8h  where h is the number of hours, C is the cost

Rosies

C = 20 +10h  where h is the number of hours, C is the Cost

1.  C = 30+8h

C = 20 +10h

Substitute the second equation into the first equation

20 +10 h = 30 +8 h

Subtract 8h from each side

20 +10 h -8h= 30 +8 h-8h

20 +2h = 30

Subtract 20 from each side

20-20 +2h = 30-20

2h = 10

Divide by 2

2h/2 =10/2

h = 5

Now find C

C = 20 +10h

C = 20 +10(5)

C = 20+50

C = 70

3.  When Rosies cost less, we want to rent from Rosies

20 +10 h <= 30 +8 h

When h is less than  5 hours

They are equal at 5 hours

4.  When we want more then 5 hours ,we should rent from sams

R <= S

5.  At exactly 5 hours the costs are the same, so we can rent from either store.

6.  Sams

C = 30+8(7) = 30 +56 = 86 dollars

Rosies

C = 20 +10(7) = 20+70 = 90 dollars

We want to rent from sams