A rectangular piece of metal is 15 in longer than it is wide. Squares with sides 3 in. long are cut from the four corners and the flaps are folded upward to form an open box. If the volume of the box is 648 in3, what were the original dimensions of the piece of metal?

Ifound this on google “that means that the graph of a function with direct variation has these features: it is a straight line: because the slope is the ratio y/x = k. it passes through the origin (0,0): because y = kx = k (0) = 0.” i hope this you for what your looking for

Ibelieve the answer is b. y=0 would make the line horizontal across the x.