Determine whether each set of ordered pairs is a function. 1. (4,1)(3,2)(2,3)(1,8) 2. (1,3)(2,3)(3,3)(4,3) 3. (1,1)(2,2)(3,3)(4,4) 4. (2,1)(4,2)(5,3)(-2,4) 5. (8,1)(8,2)(8,3)(8,4) 6. (-2,-2)(0,0)(6,6)(-8,-8)

Elements in the domain are mapped to exactly one element in the codomain, therefore: 
1. (4,1)(3,2)(2,3)(1,8) yes
2. (1,3)(2,3)(3,3)(4,3) yes
3. (1,1)(2,2)(3,3)(4,4) yes 
4. (2,1)(4,2)(5,3)(-2,4) yes
5. (8,1)(8,2)(8,3)(8,4) no!
6. (-2,-2)(0,0)(6,6)(-8,-8) yes 


:)