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Question
The point A(4, 6) is first reflected in the origin to point A’. Point A’ is then reflected in the y-axis to the point A”.
- Write down the co-ordinates of A”.
- Write down a single transformation that maps A onto A”.
Solution
i. The reflection in origin is given by MO (x, y) = (–x, –y).
A’ = reflection of A(4, 6) in the origin = (–4, –6)
The reflection in y-axis is given by My (x, y) = (–x, y).
A” = reflection of A’(–4, –6) in the y-axis = (4, –6)
ii. The reflection in x-axis is given by Mx (x, y) = (x, –y).
The reflection of A(4, 6) in x-axis is (4, –6).
Thus, the required single transformation is the reflection of A in the x-axis to the point A”.
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