Length times WidthIf the length is 3 meters and the width

is 2 meters, what is the area?A = L x W

A = 3 x 2 = 6 meters2

A, L and W are the variables. It is any letter that represents an unknown number.

1) one or more numbers or variables, and

2) one or more arithmetic operations. Examples:

x - 33 • 2n4

1m

+

1) ab 2) a • b 3) a(b) or (a)b 4) (a)(b) 5) a x b

We are not going to use the multiplication symbol any more. Why?

1)

2) x ÷ 3

x

3

Addition Subtraction Multiplication Division

Addition Subtraction Multiplication Division

sum* difference* product* quotient*

increase decrease times divided

plus minus multiplied ratio

add subtract

more than less than

total

m + 52) 7 times the product of x and t.

7xt or 7(x)(t) or 7 • x • t

3) 11 less than 4 times a number.

4n - 11

4) two more than 6 times a number.

6n + 2

5) the quotient of a number and 12.

x/2

1. 7x + 132. 7x - 133. 13 - 7x4. 13 + 7x

Answer Now

1. 28 - 3x2. 3x - 283. 28 + 3x4. 3x + 28

Answer Now

The ratio of m to rDo you have a different way of writing these?

The sum of 8 and a

2)

m

r.

1. 9 increased by twice a number

2. a number increased by nine3. twice a number decreased

by 94. 9 less than twice a number

Answer Now

1. 5x - 162. 16x + 53. 16 + 5x4. 16 - 5x

Answer Now

baseand 3 is called the

exponent or power.103 means 10 • 10 • 10

103 = 1000

Two to the first power22

Two to the second power or two squared

23

Two to the third power or two cubed2n7

Two times n to the seventh power

1. the sum of a number squared and twice a number

2. the sum of a number and twice the number

3. twice a number less than the number squared

4. the sum of a number and twice the number squared

Answer Now

1. 4 – x3

2. 4 – 3x3. 3x – 44. x3 – 4

Answer Now

222

2 • 2 = 423

2 • 2 • 2 = 82n7

We can’t evaluate because we don’t know what n equals to!!

35 = 3 • 3 • 3 • 3 • 3 = 24353 = 5 • 5 • 5 = 125

243 ≠ 125 They are not the same!