Question

Which equation represents a proportional relationship that has a constant of proportionality equal to 2?

Answer 1

you didn't give the options but constant of proportionality is a number you have to multiply x by to get y.

y=kx is the equation that expresses the proportionality of x and y

the constant of proportionality is k, so k=2

y= kx becomes y=2x

so y = 2x should be the answer

Answer 2

`y=2x`

Explanation:

We are given that

The proportion constant=k=2

We know that

Direct proportion: When one quantity increases then other quantity is also increase.When one quantity decreases then other quantity is also decrease.

Mathematical representation:Let one quantity= x and second quantity=y

`y\propto x`

`y=kx`

Where k= Proportionality constant

Substitute the value of k

`y=2x`

This is required equation which shows proportional relationship.