I see. Imagine you have f(x)=|x|. It's a V shaped graph.
Now if f(x)=|x|, 2f(x)=2|x|.
Graph Transformation Rule:
af(x), multiply y-coordinates by a.
*Ultimately, you'd still have a V shaped graph in 2f(x)=2|x|, but the y values of all the coordinates in f(x)=|x| would have to be multiplied by 2 giving you 2f(x)=2|x|.
i can't delete my answer but at first i thought it was just #7 but then i paid attention to the others and they all look like right triangles but idk fs sorry