Final answer:
The effect of the transformation (x,y) to (x,7y) is a vertical stretch without reflection.
Step-by-step explanation:
The effect of the transformation (x,y) to (x,7y) is a vertical stretch without reflection. In this transformation, the y-coordinate of every point is multiplied by 7, while the x-coordinate remains the same. This causes the graph to stretch vertically by a factor of 7, making it taller or flatter depending on the sign of y.