Math 1 Flashcards
Real number
Any number on the number line including positive, negative, zero, fractions, decimals
Integers
All positive and negative WHOLE numbers, including zero
Commutative property
Switch order (addition and multiplication)
a+b=b+a
ab=ba
*can rewrite subtraction as addition of negative
7-4=7+(-4)=(-4)+7
Associative property
Grouping (addition and multiplication)
A+(b+c)=(a+b)+c
a(bc)=(ab)c
Distributive property
A(b+c)=ab +ac
A(b-c)=ab-ac
Multiplying by zero
Anything times zero equals zero
Zero product property
If product of two numbers is zero, one factor must be zero
If ab=0, then a=0 or b=0
Dividing number by itself
If a doesn’t equal 0, then a/a=1
(Negative) - (positive)
Or
(Negative) + (negative)
Factor out negative sign
(-46)-37 = -(46+37) = -83
(Small positive) - (bigger positive)
Or
(Small positive) + (big negative)
Factor out negative and reverse order of subtraction
23-64= -(64-23)= -41
Sign rules for multiplication/division
Same sign=positive
Different sign=negative
Absolute values
Gives the distance of the number from the origin
|x-5|= distance of x from +5
|x+3|= distance of x from -3
Order of operations
GEMDAS (grouping)
Always cancel before multiplying
Work from inside out with groups
Multiplying decimals
Count number of digits to right of decimal and multiply as whole numbers
6.25 x 0.048 ; 2+3=5 decimal places
625 x 48 = 30000 = 0.3
Decimal exponents
(0.3)^3=(0.03) x (0.03) x (0.03)
Then like multiplication rules: 6 places to the right of the decimal
3^3=27 ; .000027
Dividing decimals
Slide decimal for both numbers to the right until you have two whole numbers (or until it’s easier to solve)
0.56/0.0007=5600/7=800
Fractions to decimals
2/5
0.4
Fractions to decimals
3/5
0.6