2. Mrs. Solar modeled Contractor 2’s fees with the formula y = 150 + 55x. Mrs. Solar compared Contractor 2’s fee to Contractor 1’s fee.

(a) What does the difference between 50 and 55 mean in the real-world context?

(b) What does the difference between 200 and 150 mean in the real-world context?

Contractor 1: y = 200 + 50x

Contractor 2: y = 150 + 55x

50 and 55 are the variable costs incurred in doing the project. These costs will only be implemented when x changes. X is the variable that may represent the number of hours worked, number of people added to complete the task.

200 and 150 are the fixed cost of the project. Mrs. Solar must pay the cost regardless of the changes happening in x.

For example: Both contractors need to add 15 additional people to complete the task. Then:

Contractor 1 : y = 200 + 50(15) = 200 + 750 = 950

Contractor 2 : y = 150 + 55(15) = 150 + 825 = 975 è Contractor 1 is the best option:

If x = 10 additional people

Contractor 1: y = 200 + 50(10) = 200 + 500 = 700

Contractor 2: y = 150 + 55(10) = 150 + 550 = 700 è Any contractor is the best option

If x = 5 additional people

Contractor 1: y = 200 + 50(5) = 200 + 250 = 450

Contractor 2: y = 150 + 55(5) = 150 + 275 = 425 è Contractor 2 is the best option