Question

Determine whether y varies directly with x. If so, find the constant of variation k and write the equation

Answer 1

`y=1.6x`

Explanation:

If y varies directly proportional with x, then equation is y=kx

where k is the constant of proportionality

`k=(y)/(x)`

LEts find out k

we use the table to find the value of k, divide y value by x value

`(6.4)/(4)=1.6`

`(11.2)/(7)=1.6`

`(16)/(10)=1.6`

`(20.8)/(13)=1.6`

1.6 is a constant . so k=1.6

y=kx

Replace the value of k, the equation becomes

`y=1.6 x`

Answer 2

y/x = k

6.4/4 = 1.6

11.2 / 7 =1.6

16/10 = 1.6

20.8 /13 =1.6

This is a direct variation and the constant is 1.6

y=1.6x