How do parentheses help us write algebraic expressions

so we are clear on what they mean?

For example, how do we write the algebraic expression “three less than a

number, times twenty”?

In this lesson you will learn how to write and read

algebraic expressions by using parentheses.

Let’s ReviewLet’s Review

25 - 3x - 2 I’m an algebraic

expression!

An algebraic expression contains at least one variable and

at least one operation.

Let’s ReviewLet’s ReviewThere are alternative notations to show

multiplication without using the sign “x.”

Division can be shown in two ways.

2 • x2(x)2x

4 ÷ x

4x

Let’s ReviewA Common Mistake

Forgetting to use parentheses correctly to create an expression within an expression.

Let’s ReviewCore Lesson

three less than a number, times twenty( )

x - 3 ( )

Let’s ReviewCore Lesson

(x -3) times twenty

20(x – 3)

factor factor

In this lesson you have learned how to write and read algebraic

expressions by using parentheses.

Let’s ReviewGuided Practice

Write the algebraic expression for:

eight times a number, plus five

Let’s ReviewExtension Activities

Write an algebraic expression for:

the product of 12 and x, divided by the sum of 4 and x

Let’s ReviewExtension Activities

Write the word form for:

5(25 – w) + 3w

Let’s ReviewExtension Activities

Write the following algebraic expression:

The quantity of 10 less than y, times the product of 3 and y

Let’s ReviewQuick Quiz

Write the algebraic expression for: eight times the quantity of a number plus six. Write the word form for: 15(9 _p) - 32