Mr. Brown is adding a concrete driveway to his property. The cost of the driveway is determined by the amount of concrete that needs to be installed. The expression (2x+5)(3x−7)

Question

represents the total cost of the driveway. The expression 2x+5
represents the number of cubic yards of concrete needed. What does the expression 3x−7
represent?

A.
the cost of each cubic yard of concrete

B.
the number of workers needed to install the driveway

C.
the rental cost for the machines used to install the driveway

D.
the number of hours needed to install the driveway

Answer 1

To understand what the expression \( 3x - 7 \) represents in the context of the total cost of the driveway given by the expression \( (2x + 5)(3x - 7) \), we recognize that the total cost can be interpreted as a product of two factors:

1. \( 2x + 5 \): This represents the number of cubic yards of concrete needed.
2. \( 3x - 7 \): This should represent some cost associated with installing or utilizing that concrete.

Since the total cost is obtained by multiplying the quantity (cubic yards) by a cost per unit (in this case, per cubic yard), we can infer that \( 3x - 7 \) represents the cost per cubic yard of concrete.

Thus, the expression \( 3x - 7 \) represents:

A. the cost of each cubic yard of concrete