1-3 Variables and Expressions

Objective: Evaluate expressions containing variables and translate

verbal phrases into algebraic expressions.

Find the value of each expression.

1. 54 – 42 7

Find the value of each expression.

1. 54 – 42 7 48

Find the value of each expression.

1. 54 – 42 72. 36 9 * 3

Find the value of each expression.

1. 54 – 42 72. 36 9 * 3 12

Find the value of each expression.

1. 54 – 42 72. 36 9 * 33. (40 * 2) - (6 * 11)

Find the value of each expression.

1. 54 – 42 72. 36 9 * 33. (40 * 2) - (6 * 11) 14

Find the value of each expression.

1. 54 – 42 72. 36 9 * 33. (40 * 2) - (6 * 11)

4. 37 + 38 30 - 5

Find the value of each expression.

1. 54 – 42 72. 36 9 * 33. (40 * 2) - (6 * 11)

4. 37 + 38 3 30 - 5

Find the value of each expression.

1. 54 – 42 72. 36 9 * 33. (40 * 2) - (6 * 11)

4. 37 + 38 30 - 55. 3[(18 - 3) + 4(5 + 7)]

Find the value of each expression.

1. 54 – 42 72. 36 9 * 33. (40 * 2) - (6 * 11)

4. 37 + 38 30 - 55. 3[(18 - 3) + 4(5 + 7)] 189

Find the value of each expression.

1. 54 – 42 72. 36 9 * 33. (40 * 2) - (6 * 11)

4. 37 + 38 30 - 55. 3[(18 - 3) + 4(5 + 7)]6. Write an expression that would help you find the total cost of twenty adult zoo tickets at $6 each and ten children's tickets at $2 each, Then find the total cost.

Find the value of each expression.

1. 54 – 42 72. 36 9 * 33. (40 * 2) - (6 * 11)

4. 37 + 38 30 - 55. 3[(18 - 3) + 4(5 + 7)]6. Write an expression that would help you find the total cost of twenty adult zoo tickets at $6 each and ten children's tickets at $2 each, Then find the total cost.

20(6) + 10(2)

Find the value of each expression.

1. 54 – 42 72. 36 9 * 33. (40 * 2) - (6 * 11)

4. 37 + 38 30 - 55. 3[(18 - 3) + 4(5 + 7)]6. Write an expression that would help you find the total cost of twenty adult zoo tickets at $6 each and ten children's tickets at $2 each, Then find the total cost.

20(6) + 10(2); $140

Substitution Property of Equality

For all numbers a and b, if a = b, then a may be replaced by b.

+ - x plus

sum

more than

increased by

total

in all

minus

difference

less than

subtract

decreased by

times

product

multiplied

each

of

divided

quotient

Examples

Translate each phrase into an algebraic expression.a. a number decreased by eight

Examples

Translate each phrase into an algebraic expression.a. a number decreased by eight

Let n represent the number.

Examples

Translate each phrase into an algebraic expression.a. a number decreased by eight

Let n represent the number.The words ‘decreased by’ suggests subtraction.

Examples

Translate each phrase into an algebraic expression.a. a number decreased by eight

Let n represent the number.The words ‘decreased by’ suggests subtraction.The algebraic expression is n – 8.

Examples

Translate each phrase into an algebraic expression.a. a number decreased by eight

Let n represent the number.The words ‘decreased by’ suggests subtraction.The algebraic expression is n – 8.

b. seven more than twice as many dollars.

Examples

Translate each phrase into an algebraic expression.a. a number decreased by eight

Let n represent the number.The words ‘decreased by’ suggests subtraction.The algebraic expression is n – 8.

b. seven more than twice as many dollars.Let d represent dollars.

Examples

Translate each phrase into an algebraic expression.a. a number decreased by eight

Let n represent the number.The words ‘decreased by’ suggests subtraction.The algebraic expression is n – 8.

b. seven more than twice as many dollars.Let d represent dollars.The words ‘more than’ suggest addition and the word twiceis another way of saying ‘two times’.

Examples

Translate each phrase into an algebraic expression.a. a number decreased by eight

Let n represent the number.The words ‘decreased by’ suggests subtraction.The algebraic expression is n – 8.

b. seven more than twice as many dollars.Let d represent dollars.The words ‘more than’ suggest addition and the word twiceis another way of saying ‘two times’.The algebraic expression is 7 + 2d or 2d + 7

Integration

Draw a picture representing a rectangle whose length is eight less than four times its width. Write an expression for the perimeter of the rectangle.

Integration

Draw a picture representing a rectangle whose length is eight less than four times its width. Write an expression for the perimeter of the rectangle.

2(4w – 8) + 2w