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Question
The point A(–3, 2) is reflected in the x-axis to the point A’. Point A’ is then reflected in the origin to point A”.
- Write down the co-ordinates of A”.
- Write down a single transformation that maps A onto A”.
Solution
i. The reflection in x-axis is given by Mx (x, y) = (x, –y).
A’ = reflection of A(–3, 2) in the x-axis = (–3, –2).
The reflection in origin is given by MO (x, y) = (–x, –y).
A” = reflection of A’(–3, –2) in the origin = (3, 2)
ii. The reflection in y-axis is given by My (x, y) = (–x, y).
The reflection of A(–3, 2) in y-axis is (3, 2).
Thus, the required single transformation is the reflection of A in the y-axis to the point A”.
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