Real World Linear Equation Situations and Interpretations

An electrician charges a set fee for every house call and then charges an hourly rate depending on how long the job takes. The total cost, C, of the electrician's services can be determined using the function C=65t+70, where t is the number of hours the electrician spends at the house working.

What is theY-INTERCEPT of the function and what is its interpretation in the context of the problem?

• 70; which represents the total cost for all services.

• 70; which represents the set fee for the house call.

• 65; which represents the total cost for all services.

• 65; which represents the set fee for the house call.

Bonnie pays a monthly fee of $80 at the health club and an additional $9 every time she attends a yoga class. Which expression below shows her total cost T if she attends y yoga classes this month?

• T = 80 + 9y

• T = 80y + 9

• T = 80 + 9 + y

• T = (80+9)y

Yvette has a home-based business putting on children's parties. She charges $55 to design the party and then $4 per child. Write a function rule that relates the total cost of the party to the number of children n.

• f(n) = 4 + 55n

• f(n) = 4 - 55n

• f(n) = 4n - 55

• f(n) = 55 + 4n

A T-shirt design company charges your team an initial fee of $25 to create the team's design. Each t-shirt printed with your design costs an additional $8. The equation for this situation is y = 8x + 25. Interpret the y-intercept in context.

• The additional fee of $8.

• The initial fee of $25.

• The additional fee of $25.

• The initial fee of $8.

Monica gets on an elevator in a skyscraper. The elevator starts to move at a rate of −20 ft/s. After 6 seconds on the elevator, Monica is 350 feet from the ground floor of the building. Select all that apply.

• x represents the time in seconds since Monica got on the elevator.

• The y-intercept represents the original height above the ground in feet.

• The elevator is moving up.

• The equation is y = 470 - 20x

• The equation is y = 20x + 470

Which of the following situations could be descried by the equation y= -25x + 120

• There are 120 people in the football stadium, and 25 more are entering each hour.

• A plumber charges $25 for a house call and $120 per hour.

• A teacher has 120 students. Her third period has 25 students

• There are 120 gallons of water in a tank. It releases water at a rate of 25 gallons per minute

Fernando works at a clothing store . Each week, he earns $120 plus a 25% commission on any clothing he sells . The equation shown below can be used to determine the total amount (y), in dollars, Fernando earns in a week during which he sells x dollars’ worth of clothing . y = 0 .25x + 120 The ordered pair (225, 176 .25) is a solution of the equation . What does this solution represent in the context of the situation?

• In a week during which Fernando sells $176 .25 worth of clothing, he earns a total of $225

• In a week during which Fernando sells $176 .25 worth of clothing, he earns $225 in commission

• In a week during which Fernando sells $225 worth of clothing, he earns a total of $176 .25

• In a week during which Fernando sells $225 worth of clothing, he earns $176 .25 in commission

The equation T = 0.63s + 78 can be used to determine T, the temperature in degrees, inside an oven s seconds after the over is turned on. Which statement relative to this equation is true?

• Each second the temperature increased 78 degrees

• The initial temperature inside the oven was degrees

• The temperature inside the oven in one minute was 141 degrees

• The temperature inside the oven increased by 78 degrees every 63 seconds

A cell phone company charges $60.00 a month for up to 1 gigabyte of data. The cost of additional data is $0.05 per megabyte. If d represents the number of additional megabytes used and c represents the total charges at the end of the month, which linear equation can be used to determine a user's monthly bill?

• c = 60 − 0.05d

• c = 60.05d

• c = 60d − 0.05

• c = 60 + 0.05d

Alex is selling tickets to a school play. An adult ticket costs $6.50 and a student ticket costs $4.00. Alex sells x adult tickets and 12 student tickets. Write an equation, C, to represent how much money Alex collected from selling tickets.

• C= $6.50x + $4.00(12)

• C= $6.50(12) +$4.00x

• C=$6.50x+$4.00x +12

• C=$10.50x+12