Question

Which is an equation of a direct proportion?

y= 1/2x – 2
y=3/x
y = -3x +4
y = -3x

Answer 1

y = - 3x

Explanation:

an equation involving direct proportion has the form

y = kx ← k is the constant of proportion

the only equation in this form is

y = - 3x ( with k = - 3 )