A landscaper estimates that a set of plants can be installed in 6 hours by 12 workers. The landscaper wants to finish a set of plants in 4 hours. Assuming that the variables are inversely related, how many workers should the landscaper bring to the job?

A: 8
B: 10
C: 14
D: 18

option d is the correct answer.

Step-by-step explanation:

The landscaper estimates that a set of plants can be installed in 6 hours by 12 workers.

Let h represent the number of hours and let w represent the number of workers. Assuming that the variables are inversely related, introducing a constant of variation, k, the expression becomes

h = k/w

Substituting h = 6 and w = 12 into the expression, it becomes

6 = k/12

k = 12 × 6 = 72

The expression becomes

h = 72/w

If the landscaper wants to finish a set of plants in 4 hours, the number of workers that he needs to bring to the job would be

4 = 72/w

w = 72/4 = 18

5(2x + 8) = -8x + 4

Distributive property.

10x + 40 = -8x + 4

Add 8x to both sides.

18x + 40 = 4

Subtract 40 from both sides.

18x = -36

Divide both sides by 18

x = -2