The inequality that will determine the number of months, x, that are required for the second phone to be less expensive is . The solution to the inequality is . Sal's mother would have to keep the second cell phone plan for at least months in order for it to be less expensive.

Question:

Sal is trying to determine which cell phone and service plan to buy for his mother. The first phone costs $100 and $55 per month for unlimited usage. The second phone costs $150 and $51 per month for unlimited usage.

The inequality that will determine the number of months, x, that are required for the second phone to be less expensive is .

The solution to the inequality is .

Sal’s mother would have to keep the second cell phone plan for at least months in order for it to be less expensive.

a.

b.

c. At least 13 months

Step-by-step explanation:

Given

First Phone;

(monthly)

Second Phone;

(monthly)

Solving (a): The inequality

Represent the number of months with x

The first phone is expressed as:

The second phone is expressed as:

For the second to be less expensive that the first, the inequality is:

Solving (b): Inequality Solution

Collect Like Terms

Solve for x

Solving (c): Interpret the solution in (b)

implies 13, 14, 15....

Hence, She'll keep the second phone for a period of at least 13 months

  n=   0.0000 - 0.3750 i  

  n=   0.0000 + 0.3750 i

step-by-step explanation:

one of these should be correct