Question

The variables x and y vary directly. Use the given values to write an equation that relates x and y. x = 18 y = 6

Answer 1

`y=(1)/(3)x`

Explanation:

It is given that x and y vary directly. It means y is directly proportional to x.

`y\propto x`

It can be written as

`y=kx` .... (1)

where, k is the constant of proportionality.

The given values are x=18 and y=6.

Substitute these values in the above equation.

`6=k(18)`

Divide both sides by 18.

`(6)/(18)=k`

`(1)/(3)=k`

Substitute the value of k in equation (1).

`y=(1)/(3)x`

Therefore, the required equation is
`y=(1)/(3)x`.

Answer 2

For this case it is observed that the ordered pair is (18,6)
An equation to relate both variables is
y = (1/3) x
In this case we find that the equation can be a line of slope
m = (1/3)
Note that:
y = (1/3)(18)
y=6