Describe how the graph of y= x2 can be transformed to the graph of the given equation. (2 points) y = x2 + 13 Shift the graph of y = x2 right 13 units. Shift the graph of y = x2 left 13 units. Shift the graph of y = x2 down 13 units. Shift the graph of y = x2 up 13 units.