Question

Which graph represents a function with direct variation?

A coordinate plane with a U shaped line graphed with the minimum at (0, 0).
A coordinate plane with a V shaped line graphed with the minimum at (0, 0).
A coordinate plane with a line passing through (negative 4, 2), (0, 0) and (4, negative 2).
A coordinate plane with a line passing through (negative 2, negative 3), (0, 1) and (1, 3).

Answer 1

Direct variation means y = kx (a straight line through the origin). The third graph (the line through (-4, 2), (0, 0), (4, -2)) fits that: it's a line through (0,0) with slope k = -1/2, so y = (-1/2)x.