Coefficients and Variables Lesson #27

Variables, Coefficients & Constants

• A variable is a letter that represents an unknown value

• A coefficient is a number directly in front of a variable. It is being multiplied by the variable.

• A constant is a number that is not connected to any variables.

Coefficients and Variables

Variables, or letters, are values in math that are not yet defined, or given a value. While coefficients are the numbers that are found directly in front of the variable.

Example: 2x

Coefficient = 2 Variable: x

Example: 36m

Coefficient = 36 Variable: m

Multiple Choice

What is the coefficient of the following:

29a

• a

• 29a

• 29

• There is no coefficient

Multiple Choice

Which of the following is the variable:

11L

• 11

• L

• There is no variable

• 11L

Variables

Letters are used in math to represent a value that is changing and at times the values is unknown.

Can you think of a time that something was changing constantly or created a value that was not known?

One step equations

In one step equations we practiced how to solve by isolating or getting a variable alone on side of the equal sign using the process of inverses. Today we want to focus on identifying the coefficients and variables that we have to combine using the same inverse idea.

One step equations (continued)

Example: 3z = 2z - 45 Step 1: use the inverse of the coefficient

-2z -2z

1z = -45 By using the inverse of the coefficient

that is not isolated we are able to solve

our equation. Where z = -45

Multiple Choice

What coefficient should we take the inverse of?

3t=-2t+17

• 2

• 2t

• 3

• 3 & 17

Multiple Choice

What coefficient should take the inverse of?

7p-9=8p

• 8

• 8p

• 7

• 7p