1. Section 2-2 Linear Equations Objective:
To graph a relation, state its domain and range, and determine if it is a function.
To find values of functions for given elements of the domain.
Algebra II

2. Independent vs. Dependent
Independent Variable – usually graphed on the horizontal or x-axis
Dependent Variable – usually graphed on the vertical or y-axis
The speed of sound through air.
Algebra II

3. Speed of Sound Graph

4. Standard Form of a Linear Equation
Ax + By = C
Algebra II

5. Example 1a
Write this equation in standard form where A, B, and C are integers whose greatest common factor is 1. Identify A, B, and C.
y = -5x + 6
Algebra II

6. Example 1b
Write this equation in standard form where A, B, and C are integers whose greatest common factor is 1. Identify A, B, and C.
Algebra II

7. Example 1c
Write this equation in standard form where A, B, and C are integers whose greatest common factor is 1. Identify A, B, and C.
5x – 10y = 25
Algebra II

8. Definition of a Linear Function
Algebra II

9. Example 2 State whether each function is a linear function.
a. f(x) = 4x + 5
b. f(x) = x3 + 2
c. f(x) = 9 – 6x
Algebra II

10. Intercepts Graphing Method
The x-intercept is the point at which the graph crosses the x-axis.
The y-intercept is the point at which the graph crosses the y-axis.
Algebra II

11. Example 3
Graph 5x – 3y = 15 using the x- and y-intercepts.
The x-intercept is the value of x when y is 0.
The y-intercept is the value of y when x is 0.
( , 0)
(0, )
5x – 3y = 15
Algebra II

12. Example 3 cont.
( , 0)
(0, )
5x – 3y = 15

13. Homework
2-2 pg 77 #18-45 by 3’s
Algebra II