Question

Antwan is purchasing a cell phone plan. The flat
cost of the plan is $50.00 per month, and there
is an additional fee of $20.00 per phone line.
Using a table and graph, determine how many
phone lines are on the plan if Antwan pays $150
per month.

Answer 1

To determine how many phone lines are on the plan if Antwan pays $150 per month, we can create an equation based on the information given.

The total monthly cost \( C \) can be represented as:

\[
C = 50 + 20n
\]

where:
- \( C \) is the total monthly cost,
- \( 50 \) is the flat cost,
- \( n \) is the number of phone lines,
- \( 20n \) is the additional cost for the phone lines.

Now we can set the equation equal to $150 and solve for \( n \):

\[
150 = 50 + 20n
\]

Subtract 50 from both sides:

\[
100 = 20n
\]

Now, divide by 20:

\[
n = \frac{100}{20} = 5
\]

Thus, Antwan can have **5 phone lines** on the plan if he pays $150 per month.

### Table Representation

Now we can create a table to show the breakdown of costs with varying numbers of phone lines.

| Number of Phone Lines (n) | Total Cost (C) |
|---------------------------|------------------|
| 0 | $50 |
| 1 | $70 |
| 2 | $90 |
| 3 | $110 |
| 4 | $130 |
| 5 | $150 |
| 6 | $170 |

### Graph Representation

To create a graph, we would plot the number of phone lines on the x-axis and the total cost on the y-axis. The points based on the above table would be:

- (0, 50)
- (1, 70)
- (2, 90)
- (3, 110)
- (4, 130)
- (5, 150)
- (6, 170)

### Conclusion
In conclusion, based on the calculations, Antwan pays $150 a month for 5 phone lines under the plan.