Identifying
Linear
Functions and
Equations
Objective: I can and I will identify
a linear function.
What is a linear function?
- What do we remember about functions?
- A linear function is a function whose graph forms a
straight line.
Ex. 1) Graph - Is it a linear function?
y
y
x
x
x
Ex. 2) Table - Is it a linear function?
X
Y
X
Y
X
Y
0
-3
-4
13
-2
7
4
0
-2
1
-1
4
8
3
0
-3
0
1
12
6
2
1
1
-2
16
9
4
13
2
-5
Ex. 3) Ordered Pairs – Is it a linear function?
(2, 4), (5, 3), (8, 2), (11, 1)
(-10, 10), (-5, 4), (0,2), (5, 0)
Standard Form of a Linear Equation
Ax + By = C
•A, B, and C are real numbers.
•A and B are not both 0.
When a linear equation is written in standard form:
•x and y both have exponents of 1
•x and y are not multiplied together
•x and y aren’t denominators, exponents, or radical signs.
Is it a Linear Function - Standard Form
x = 2y + 4
y
x
Ex. 4) Is it a Linear Function - Standard Form
y = 5x - 9
y
x
Weather…
 The National Weather Service releases weather balloons twice
daily at over 90 locations in the United States in order to collect
data for meteorologists. The height (h) in feet of a balloon is a
function the time (t) in seconds after the balloon is released.
 Make a table showing the height of a balloon after (t) seconds
for t=0 through t=10.
 A balloon bursts after a flight of about 7200 seconds.
the function and identify the domain and range.
Graph
Balloon being released…
h=14t + 5
Practice
Pg. 304 # 1 - 14