A+(b+c)=(a+b)+c what property is this? the options are as follows
identity property of multiplication
associative property of multiplication
identity prop. of addition
multiplicative inverse prop.
additive inverse prop.
commutative prop of addition
commutative prop of multiplication
transitive property
properties

Given: lines a and b are parallel and line c is a transversal. prove: 2 is supplementary to 8 what is the missing reason in the proof? statement reason 1. a || b, is a transv 1. given 2. ∠6 ≅ ∠2 2. ? 3. m∠6 = m∠2 3. def. of congruent 4. ∠6 is supp. to ∠8 4. def. of linear pair 5. ∠2 is supp. to ∠8 5. congruent supplements theorem corresponding angles theorem alternate interior angles theorem vertical angles theorem alternate exterior angles theorem