Writing Linear Functions

Writing Linear Functions

Writing Linear Functions

Practice Problems

Multiple Choice

To prepare for a recent road trip, Jill filled up her 19-gallon tank. She estimates that her SUV will use about three gallons per hour. Write an equation to model the amount of gasoline, G, remaining in her tank after t hours.

• G=19 – 3t

• G=19 + 3t

• G=3 - 19t

• G=3 + 19t

Multiple Choice

The temperature outside is currently 68°F and falling at a steady rate of 4 degrees every hour. Write a linear equation that relates the Fahrenheit temperature, F, to the time in hours, t, it has been falling.

• F = -4x + 68

• F(t) = -4t + 68

• F(t) = 4t + 68

• F(t) = 4x + 64

Multiple Choice

Jen charges $7.50 for every hour, h, she babysits. Write a function, f(h), to represent the total amount Jen would make babysitting h, hours.

• f(h) = 1h + 7.5

• y = 7.5x

• f(h) = 7.5h

• y = 8h + 7.5

Multiple Choice

Andy has $310 in his account. Each week, w, he withdraws $30 for his expenses. Write a linear equation to represent the scenario.

• f(x) = -310w + 30

• y = -30w + 310

• y = 30w + 310

• f(x) = -30x + 310

Multiple Choice

Connor wants to attend the town carnival. The price of admission to the carnival is $4.50, and each ride costs an additional 79 cents. Which table is the correct representation for this scenario?

Multiple Choice

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, write a linear equation to determine a user's monthly bill?

• C(d) = 0.05d + 60

• y = 0.05x + 60

• C(d) = 60d + 0.05

• y = 60x + 0.05

Multiple Choice

Kyle is starting an exercise program. The FIRST day he will spend 28 minutes on a treadmill. He will increase his time on the treadmill by 4 minutes each day. Write an equation for T(d), the time, in minutes, on the treadmill on day d.

• T(d) = 4d + 28

• T(d) = 4d + 24

• y = 28d + 4

• y = 24d + 4

Multiple Choice

Mr. Cook is saving money in an account. At the beginning of the year, he has $56 in savings and puts in another $4 per week. Write a function f(x) that models the total amount in the savings account after x, weeks.

• f(x) = 56 + 4x

• f(x) = 56x + 4

• y = 4x + 56

• y = -56 - 4x

Fill in the Blanks

If the linear equation y = -2x + 198 represents Nathan's total weight after x weeks, how much will his weigh after 6 weeks?

Fill in the Blanks

If the linear equation y = 25x + 75 represents the amount of money saved after x months, how much money will be saved after 9 months?

Multiple Choice

This graph shows the increase in oven temperature over time (minutes).

What is the meaning of the y-intercept?

• The temperature started at 0°

• The temperature started at 70°

• The temperature increased at a rate of 40° per minute

• The temperature increased at a rate of 150° per minute