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

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

Answer 2

Answer:

$y=\dfrac{1}{3}x$

Step-by-step 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.

$\dfrac{6}{18}=k$

$\dfrac{1}{3}=k$

Substitute the value of k in equation (1).

$y=\dfrac{1}{3}x$

Therefore, the required equation is $y=\dfrac{1}{3}x$.