3-1 Graphing Linear EquationsI can:

• Determine whether an equation is linear.

• Identify the x & y-intercepts from a graph.

• Find x & y-intercepts from an equation.

• Graph a linear equation using x & y-intercepts.

• Identify x & y-intercepts from a table.• Graph a linear equation using a table.

A functions whose graph forms a straight line.Example 1: Determine whether each graph represents a function. If the graph does represent a function, is the function linear?

Linear Function

Any equation that can be written in the standard form:

Standard Form of a Linear Equation

NOTICE: both have exponents of 1 are not multiplied together do not appear in denominators, exponents, or radical

signs.

Linear Equation

Linear vs. Not Linear

LINEAR Not LINEAR

a) b)

c) d)

e)

Example 2: Tell whether each graph is linear. If it is, write it in standard form.

1) Where the line crosses the x-axis2)

x-intercept

1) Where the line crosses the y-axis2)

y-intercept

You can easily find the x & y intercepts and graph the line using those two points.

Why is standard form useful?

Example 3: Given the graph, state the x & y intercepts.

a. b. c.

x-intercept:

y-intercept:

x-intercept:

y-intercept:

x-intercept:

y-intercept:

Example 4: 1) find the x& y intercepts 2) graph the line using the intercepts.

a.

Example 4: 1) find the x& y intercepts 2) graph the line using the intercepts.

b.

Example 4: 1) find the x& y intercepts 2) graph the line using the intercepts.

c.

Example 4: 1) find the x& y intercepts 2) graph the line using the intercepts.

d.

Example 5: Calculate the x & y intercepts for the following lines:

a ¿ 𝑦=4 𝑥+2

Example 5: Calculate the x & y intercepts for the following lines:

b¿−8 𝑥−10 𝑦=−40

Example 5: Calculate the x & y intercepts for the following lines:

6

Example 6: The table shows the function relating the distance to an amusement park in miles and the time in hours the Torres family has driven. Find the x & y – intercepts and their meaning in this situation.

a.

Example 7: Graph each equation by making an table.

b.

Example 7: Graph each equation by making an equation.

Practice

Page 159-160: 1-10, 13-15, 21, 22, 23-27 odd,

Homework