To find out which landscaping company is cheaper for Charlotte, we need to write equations for each company based on their charges and then evaluate those equations at \( t = 7 \) hours.
Company A:
- Charges: $50 per hour
- Equipment fee: $100
The total cost for Company A, represented as \( A(t) \), for \( t \) hours can be expressed with the formula: \[ A(t) = 50t + 100 \]
Company B:
- Charges: $25 per hour
- Equipment fee: $200
The total cost for Company B, represented as \( B(t) \), for \( t \) hours is: \[ B(t) = 25t + 200 \]
Calculating Costs for 7 Hours:
Now, we will compute the costs for both companies when \( t = 7 \) hours.
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For Company A: \[ A(7) = 50 \times 7 + 100 = 350 + 100 = 450 \]
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For Company B: \[ B(7) = 25 \times 7 + 200 = 175 + 200 = 375 \]
Comparison:
- Total cost for Company A for 7 hours: $450
- Total cost for Company B for 7 hours: $375
Conclusion:
Since \( B(7) = 375 < A(7) = 450 \), Company B is the cheaper option for Charlotte if she needs 7 hours of landscaping services.
Graphing the Functions:
To visualize this, you could graph the functions \( A(t) = 50t + 100 \) and \( B(t) = 25t + 200 \).
- For Company A, the graph is a line with a slope of 50 that starts at 100 on the y-axis.
- For Company B, the graph is a line with a slope of 25 that starts at 200 on the y-axis.
The intersection of these two lines will give the point where both companies charge the same price. Calculating that point involves setting \( A(t) = B(t) \): \[ 50t + 100 = 25t + 200 \] Solving for \( t \): \[ 50t - 25t = 200 - 100 \ 25t = 100 \ t = 4 \] At \( t = 4 \), both companies charge the same, which can be calculated as follows: \[ A(4) = 50 \times 4 + 100 = 200 + 100 = 300 \ B(4) = 25 \times 4 + 200 = 100 + 200 = 300 \] Thus, for any \( t < 4 \), Company B is cheaper and for \( t > 4 \), Company A becomes the cheaper option.