Equations, Tables, and Graphs

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Lesson 8-4 Warm-Up
LESSON 8-4 Warm Up
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Lesson 8-4 Warm-Up
LESSON 8-4 Warm Up
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Graphing Linear Functions (8-4)

• To graph any function
• Make a function table (x y table) where the x
  values (horizontal axis on the graph) are the
  input values (also called independent values) and
  the y values are the output (or dependent)
  values. Make up your own x, or input values, and
  find the y, or output values for those x values.
  Write the x and y solutionsas ordered pairs.
• Plot those (x, y) pairs and connect the points
  together.
• Example Graph y - x 12
• Substitute your own x (input) values
  into the equation and find the corresponding
  y values.
• Write the solutions to the equations as
  ordered pairs (x, y)

• How do you graph a linear (line) function?

1 3
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Graphing Linear Functions (8-4)

• Plot the ordered pairs from your
  function table..
• Connect the dots (a linear function in
  which x is to the first power, or x1 will
  form a line)

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Graphing Linear Functions
LESSON 8-4
Additional Examples
Suppose you buy a bag of food for your dog
every week. Use the table below to make a graph
of the cost of the dog food.
Number of Weeks 1 2 3 4
Cost of Dog Food 4 8 12 16
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Graphing Linear Functions
LESSON 8-4
Additional Examples
Graph the linear equation y x 3, where y
represents the pressure inside a deflating
balloon after x seconds.
Each point (x, y) on the graph represents a
solution of the equation. For example, the point
(1, 2) means that after 1 second the pressure
inside the balloon is 2 units of pressure.
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Graphing Linear Functions
LESSON 8-4
Additional Examples
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Graphing Linear Functions
LESSON 8-4
Additional Examples
Graph the function y x 2.
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Graphing Linear Functions
LESSON 8-4
Lesson Quiz
1. Complete the table and graph the function
given the rule Output Input
(4). 2. Make a table and graph the
function y 1.