Explain why when you reflect a point across the line y=x, the x−coordinate and the y−coordinate change places, and when you reflect a point across the line y = −x, the x−coordinate and the y−coordinate change places and their signs are changed.
The (x,y) is like a mirror reflecting across the plane. When it moves it goes opposite (y,x). We move over the y axis and we get a negitive because of the negative cordinate plane.
