Question

Must explain not just a straight-up one answer or reported

cell phone company charges $50 plus $40 per line each month. Luke must spend under $170 on his family's cell phone bill each month. How many cell phones can his family have?

A. Write an inequality to solve this situation.

B. Solve the inequality to answer how many cell phones this family can have.

C. Explain how you solved the inequality.

Answer 1

Explanation:

Write an inequality:

Let x be the number of cell phones Luke's family can have.

Since $50 will always be charged, then let's add 50 to our inequality, as well as <170 because the amount spent needs to be less than 170.

50<170

Per line, it's $40, and if x is the number of cell phones Luke's family can have, it will be 40x. We can add this to the total cost.

50+40x<170

Solve the inequality + explanation:

50+40x<170

1. Subtraction property of equality

Since the subtraction property of equality states that if you subtract the same amount from each side it will be equal, subtract 50 to isolate the variable.

50+40x<170

-50 -50

40x<170

2. Division property of equality

Since the division property of equality states that if you divide the same amount from each side it will be equal, divide by 40.

40x<170

170/40=4.25

Since we cannot have 1/4 of a phone, we need to round down to 4.

The most phones Luke's family can have is 4.