Lesson 1-7: Parts of an Expression

Lesson 1-7: Parts of an Expression

How can you describe the parts of an expression?

There are special words you can use to identify parts of numerical expressions and algebraic expressions. Remember that the fraction bar also means divide.

Example:

• Each part of an expression that is separated by a plus (+) or minus (-) sign is called a term

• This expression has three terms. What are they?

•  $12r,\ \frac{r}{2},\ -19$  

Multiple Choice

What do we call a part of an expression that is separated by a plus or minus sign?

• Coefficient

• Equation

• Operation

• Term

Multiple Choice

How many terms are in the expression 14 + 7w - 4z

• 1

• 2

• 3

• 4

What about this?

• A coefficient is a number that is multiplied by a variable

• In the term 12r, 12 is the coefficient of r

• In this product, 12 and r are both factors

Multiple Choice

What do we call a number that is multiplied by a variable?

• Coefficient

• Operation

• Term

• Variable

Multiple Choice

What is the coefficient in 5y?

• 5

• y

Multiple Choice

What is the variable in 5y?

• 5

• y

Let's try describing some expressions!

Multiple Choice

Describe the expression b + 10

• 10 greater than b

• 10 less than b

• b divided by 10

• the product of b and 10

b + 10

We can describe this expression by saying 10 greater than b. Greater than hints that I am adding. Since addition is commutative, the order in which I add b and 10 does not change my answer!

Multiple Choice

Describe the expresssion 6(s+2)

• the product of 6, s, and 2

• 6 divided by the sum of s and 2

• 6 times the sum of s and 2

• 6 minus s plus 2

6(s+2)

We are multiplying the sum of s + 2 (reminder: sum tells us we are adding).

Multiple Choice

Describe the expression $r\div9$  

• r plus 9

• r minus 9

• r times 9 

• r divided by 9

 $r\div9$  

Keep in mind that order matters! 
 $r\div9$  is not the same thing as  $9\div r$ 

Let's work on identifying terms in expressions!

Multiple Choice

How many terms are in the expression  $13+7-1$  

• 1

• 2

• 3

• 4

 $13+7-1$  

This expression has three terms!
13
7
1

Multiple Choice

How many terms are in the expression $2l+2w$  

• 1

• 2

• 3

• 4

 $2l+2w$  

There are two terms in this expression!
2l
2w

Multiple Choice

How many terms are in the expression $\frac{9}{5}c+32$  

• 1

• 2

• 3

• 4

 $\frac{9}{5}c+32$  

There are two terms in this expression!
 $\frac{9}{5}c$  
32