Exercise 8 Page 198

Two quantities are proportional when all of the ratios relating the quantities are equivalent. For each pair of x and y we will find the value of the ratio y x. If these values are the same, the quantities are proportional.

x	y	y/x	Value
2	4	4/2	2/1
4	2	2/4	1/2
6	1	1/6	1/6
8	1/2	.1 /2./8	1/16
10	1/4	.1 /4./10	1/40

Notice that the value of the fraction yx are different for all pairs of x and y. Therefore, x and y are not proportional.