12.2: Properties of Real Numbers
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Commutative Property
Addition
a+b=b+a
3+4=4+3
Multiplication
ab=ba
4⋅3=3⋅4
Associative Property
Addition
a+(b+c)=(a+b)+c
4+(3+5)=(4+3)+5
Multiplication
a(bc)=(ab)c
4(3⋅5)=(4⋅3)5
Distributive Property
a(b+c)=ab+ac
4(x+3)=4x+12
(b+c)a=ab+bc
(x+3)4=4x+12
Properties of Zero
a⋅0=0
0⋅a=0
If a=≠0, then 0a=0 and a0=0 is undefined.
Double Negative Property
−(−a)=a