Page 3 - Lesson Notes
P. 3

Reflection in origin (0, 0)

               In the coordinate plane, we can use any point as the point of reflection. The most commonly
               used point is “origin”.
               Example





























               Let ABC be the triangle, and the coordinates are A(1,4), B(1,1), and C(5,1). After the point of
               reflection in origin, the pre-image ABC is transformed into A’B’C’. When you draw a line segment
               connecting the points A and A’, the origin should be the midpoint of the line.

               Therefore,
               The point of reflection in origin (0, 0), the image of the point (x, y) is (-x, -y).


































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