Properties of Addition: commutative property of addition Also called order property of addition. This property means that addends can be added in any order and the sum is always the same. associative property of addition The property that states that when adding three or more real numbers, the sum is always the same regardless of their grouping. That is, (a + b) + c = a + (b + c) additive identity The number zero is called the additive identity because the addition of zero does not change the value of any number, that is, x+0=0+x=x for any given real number x. additive inverse The additive inverse of a number is the opposite of that number, that is, the additive inverse of a number x is -x. The sum of a number and its additive inverse is always zero, that is, x + (-x) = 0. Properties of Multiplication: associative property of multiplication The property that states that when multiplying three or more real numbers, the product is always the same regardless of their grouping. That is, (a × b) × c = a × (b × c) commutative property of multiplication Also called order property of multiplication. This property means that factors can be multiplied in any order and the product is always the same. distributive property of multiplication over addition The distributive property states that multiplying a sum by a number gives the same result as multiplying each addend by the number and then adding the products together. 4 × (2 + 3) = 4 × 2 + 4 × 3 multiplicative identity The number one is called the multiplicative identity because the multiplication of one does not change the value of any number, that is, x times 1 = 1 times x = x for any given real number x. multiplicative inverse The reciprocal of a given number or expression Name that Property! Answer Sheet 1. Commutative Property of Addition 2. Additive Identity 3. 4. 5. 6. 7. 8. 9. 12+4+1=4+1+12 5+2=2+5 -­‐2+0=-­‐2 8+0=8 Additive Inverse -­‐4+4=0 1/8+-­‐1/8=0 Associative Property of Addition (2+3)+4=2+(3+4) (8+14)+5=8+(14) Associative Property of 9x (2x12)=(9x2)x12 Multiplication (3x2)x1=3x(2x1) Commutative Property of 3x4=4x3 Multiplication 3x2x4=2x3x4 Distributive Property of 8(x+2)=8x+16 Multiplication Over/Across 3x+6=3(x+2) Addition Multiplicative Inverse -­‐1/2 x (-­‐2)= 1 3x1/3= 1 Multiplicative Identity 1/5X1=1/5 -­‐3X1=-­‐3