Is this proof correct? if not, what is it? SSS, AAS, ASA, SAS

Simonne used the following steps to simplify the given expression. 12 - 3(-2x + 4) step 1: 12 + (–3)·(–2x) + (–3)·(4) step 2: 12 + 6x + (–12) step 3: 12 + (–12) + 6x step 4: 0 + 6x step 5: 6x what property of real numbers was used to transition from step 3 to step 4? a. identity property of addition b. inverse property of addition c. associative property of addition d. commutative property of addition

The sum of these consecutive integers is equal to 9 less than 4 times the least of the integer. find the three integers

How do you determine if an ordered pair is a solution to a given equation?