Modeling Linear Expressions

Lesson 2.2 Modeling Linear Function

Slope-intercept Form

Objectives

• Understand that a linear function has a constant rate of change (slope)

• Understand the meaning of x and y intercepts

Task 1

Suppose that the water level of a river is 34 feet and that it is receding at a rate of 0.5 foot per day. Write an equation for the water level, L, after d days.

Task 2

Nathan's school is located 3 miles from his house. He is riding his scooter to school at a rate of 6 miles per hour. Write an equation to represent the problem situation.

Task 3

A plumber charges $25 for a service call plus $50 per hour of service. Write an equation in slope-intercept form for the cost, C, after h hours of service.

Multiple Choice

For babysitting, Nicole charges a flat fee of $3, plus $5 per hour. Select the independent quantity in this problem situation.

• Time (hours)

• Price (dollars)

• $3

• $5

Multiple Choice

For babysitting, Nicole charges a flat fee of $3, plus $5 per hour. Select the dependent quantity in this problem situation.

• Time (hours)

• Cost (dollars)

• $3

• $5

Multiple Choice

For babysitting, Nicole charges a flat fee of $3, plus $5 per hour. What is the slope? What is its meaning in the context of the problem?

• $5

  The cost of each hour of babysitting

• $3

  The initial fee for babysitting

Multiple Choice

For babysitting, Nicole charges a flat fee of $3, plus $5 per hour. What is the y-intercept? What is its meaning in the context of the problem?

• $5

  The price of each hour of babysitting

• $3

  The initial fee for babysitting

Open Ended

For babysitting, Nicole charges a flat fee of $3, plus $5 per hour. Write an equation for the cost, C, after h hours of babysitting.