This is the table for the billions of dollars in book sales for the first four years after 1990. The equation y=19(1.057)x represents book sales in billions of dollars since 1990. Let x represent the number of years. Let x=0 represent book sales in 1990. They have been rounded to the nearest whole number. Years after 1990 x 1 2 3 4
Billions of dollars y 20 21 22 23

Which column is incorrect?

1

2

3

4

1.4

2.3

step-by-step explanation:

the formula for the constant of variation is

y= kx

divide each side by x

y/x =kx/x

y/x =k

we know a and y

1.   y/x = k

4/1 =4

check the other values to make sure they are the same

8/2 = 4   12/3 =4   and 16/4 =4  

the constant of variation is 4

2.   y/x = k

3/1 =3

check the other values to make sure they are the same

6/2 = 3   9/3 =3   and 12/4 =3  

the constant of variation is 3

lo.lll

step-by-step explanation: