Below are tables of values for four functions. Determine whether each table could represent an affine function. (Affine functions are also sometimes called linear functions in some textbooks.)

y = 2	21	15	9	3	3
y = 1	15	9	3	3	9
y = 0	9	3	3	9	15
y = -1	3	3	9	15	21
y = -2	3	9	15	21	27
y / x	x = -2	x = -1	x = 0	x = 1	x = 2

Could this be an affine function? ? Yes No

y = 2	14	-7	-14	-7	14
y = 1	29	8	1	8	29
y = 0	34	13	6	13	34
y = -1	29	8	1	8	29
y = -2	14	-7	-14	-7	14
y / x	x = -2	x = -1	x = 0	x = 1	x = 2

Could this be an affine function? ? Yes No

y = 2	16	16	16	16	16
y = 1	4	4	4	4	4
y = 0	0	0	0	0	0
y = -1	4	4	4	4	4
y = -2	16	16	16	16	16
y / x	x = -2	x = -1	x = 0	x = 1	x = 2

Could this be an affine function? ? Yes No

y = 2	-13	-8	-3	2	7
y = 1	-10	-5	0	5	10
y = 0	-7	-2	3	8	13
y = -1	-4	1	6	11	16
y = -2	-1	4	9	14	19
y / x	x = -2	x = -1	x = 0	x = 1	x = 2

Could this be an affine function? ? Yes No