Each answer choice below represents a relation by a set of ordered pairs. In which of the answer choices is the relation a function? Select all correct answers.

Select all that apply:

{(−3,0),(3,−1),(4,10),(−2,0)}
{(5,0),(−2,−1),(−2,10),(2,9)}
{(8,8),(6,9),(1,−2),(−2,9)}
{(−5,7),(−3,−3),(8,−1),(8,5)}
{(7,−5),(6,9),(6,3),(−1,−1)}

Scenario: susan wants to make 2 square flags to sell at a crafts fair. the fabric she wants to buy is 3 meters wide. she doesn't want any fabric left over. what's the least amount of fabric she should buy? question: which equation will susan solve her problem? note: let x represent the length of 1 side of the flag. options: 1) 2x^2 = 4x 2) 8 +2x = 2(4x) 3) 2 * 2 = 4 * 2 4) 4x^2 -2x = 0