assocating three or more addends or factors in a different fashion will not change the sum or product.

(3+7) +5

The order in which addends are added or factors are multiplied does not determine the sum or product

9x6 or 6x9

a(b+c)=(axb)+ (axc)

6x(47)=(6x40)+(6x7)

adding zero to any number will not change the number

87+0= 87

those that can be written as fractions

12 can be written as 12/1

decimals that come to an end when represented exactly

2.125

decimals that repeat a pattern endlessly

3.333333.....

What is the symbol pi?

Divide the numerator by the demoninator

1/4 becomes 0.25 when 1 is divided by 4

shift the decimal point two places to the right

0.135 becomes 13.5%

shift the decimal point two places to the left

98% becomes 0.98

put the percent over 100, then reduce

20/100 reduces to 1/5

What is ratio notation?

an alternative method for showing fractions

2/5 is rewritten as 2 to 5 or 2:5

a symbol that represents an unknown value

x

The word is suggests an equal sign,

of and product may suggest multiplication, sum refers to addition, difference suggests subtraction, quotient refers to division.

only like algebraic terms can be added or subtracted to produce similar expressions

2x + 3x = 5x

algrebraic expressions of two terms

First, Outer, Inner, Last

(x+3)x (2x-5)

multipy x by 2x (first), then x by -5(outer), then 3 by 2x(Inner), and 3 by 5 (last)

2x^2, -5x, 6x, and -15= 2x^2 +x-15

rewriting any common factor out of the equation, to simplify it

5x^2-10  factored out 5(x^2-2)

a line

a line over AB for example

an arrow

an arrow over XY, meaning a point originates at point X and extends through point Y

What is the equation for the circumference of a circle?

c= pi x d

or

c= 2pi x r

distance around the object,

for a square: 4x measurement of side

for a rectangle: 2xlength + 2x width

it is always cubed, side x side x side

or a rectangle, width x length x height

a^2 + b^2 = c^2

for exmple: 2^2 + 6^2 = 40

the square root of 40 is 6.3

 so the hypotenuse of the triangle is 6.3