How can you show that two quantities have a proportional relationship?

If they can be expressed in the form of y=kx, they are proportional. In other words, these quantities always maintain the same ratio. That is, when you divide any pair of the two values, you always get the same number k.

idk

step-by-step explanation:

idk

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so: