Variables and Expressions

LESSON 11

REVIEW!

• Vocabulary

• Variable:

• a symbol used to represent numbers or values.

• Algebraic Expression:

• one or more numbers and variables with one or more arithmetic operations

WHAT DO EXPRESSIONS LOOK LIKE?

• Here are some examples

5x

3c – 7

4 + p/2

Can you give some examples?

WRITING EXPRESSIONS - ADDING

1. Add 9 and 3 9 + 3

2. The sum of x and 4 x + 4

3. x more than -2 (switch) -2 + x

4. 8 plus y 8 + y

Can you think of any other words that are the same as adding??

WRITING EXPRESSIONS - SUBTRACTING

1. Subtract x from y y – x

2. Subtract x and y x – y

3. The difference of c and 4 c – 4

4. 5 less than t (switch) t – 5

5. 8 minus y 8 – y

Can you think of any other words that are the same as subtracting??

WRITING EXPRESSIONS - MULTIPLYING

1. Multiply -4 and h -4h

2. The product of 3x and 7 7(3x)

3. 9t multiplied by -3z 9t(-3z)

4. 8c times -2y (8c)(-2y)

Can you think of any other words that are the same as multiplying??

WRITING EXPRESSIONS - DIVIDING

1. Divide 8x and 6y 8x ÷ 6y

2. The quotient of 9 and 3x 9 ÷ 3x

3. 5y divided by -2 5y ÷ -2

Can you think of any other words that are the same as dividing??

WRITING EXPRESSIONS - EXPONENTS

1. A number squared y2

2. The cube (or third power) of a number 3x3

Can you think of any other words that are used for exponents??

PRACTICE TIME!

• Write the expression for the following

1. The sum of a x and 3 times y squared

2. 5 decreased x to the third power

3. The quotient of 5 plus y and 3 decreased by x

4. 8x + 2

5. 3 ÷ 2y2