Question

Is y=-3x a direct variation

Answer 1

Yes it is a direct variation because it is in the form y = k*x. In this case, k = -3

The graph is a straight line through (0,0) and (1,-3). The fact that this is a straight line going through the origin (0,0) is a visual way to determine that it's a direct variation equation.

Answer 2

Hey!
Yes it is. The formula for a direct variation question is y = kx
k = -3
Also direct variations always go through the origin which is (0, 0), so you can always graph and check!
Hope this helps!