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Question
Attempt this question on graph paper.
- Plot A (3, 2) and B (5, 4) on graph paper. Take 2 cm = 1 unit on both the axes.
- Reflect A and B in the x-axis to A’ and B’ respectively. Plot these points also on the same graph paper.
- Write down:
- the geometrical name of the figure ABB’A’;
- the measure of angle ABB’;
- the image of A” of A, when A is reflected in the origin.
- the single transformation that maps A’ to A”.
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Solution
- ∵ From the graph, we can say that
- ∵ Mx (x, y) = (x, –y)
Thus, Mx (3, 2) = (3, –2) and Mx (5, 4) = (5, –4) -
- an isosceles trapezium
- 45°
- ∵ Mo (x, y) = (–x, –y)
- Now A' (3, –2) `\implies` A" (–3, –2) ...[∵ My (x, y) = (–x, y)]
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