Question

What is the equation of the line? Be sure to scroll down first to see all answer options. (-3,9) (0,0)

Answer 1

y = -3x

Explanation:

it's what the test said

Answer 2

Option D
`y=-3x`

Explanation:

we have the points

(-3,9) and (0,0)

we know that

A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form
`y/x=k` or
`y=kx`

In a proportional relationship the constant of proportionality k is equal to the slope m of the line and the line passes through the origin

In this problem the line passes through the origin, then the line represent a direct variation

Find the constant of proportionality k

`k=y/x`

For the point (-3,9)

`k=9/-3=-3`

so

the equation is

`y=-3x`