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Question
A triangle ABC lies in the co-ordinate plane. The co-ordinates of its vertices are A (2, 3), B ( 4,-4) and C (6 ,-7). This triangle is reflected in the line y=O onto LA'B'C'. LA'B'C' is then reflected in the origin ontolA"B"C". Write down the co-ordinates of LA'B'C' and LA "B" C".
Solution
A = (2, 3); B = (4,-4); C = (6,-7)
Co-ordinates of LA'B'C' under reflection in the line y=O:
A'= (2,-3); B' = (4, 4); C' = (6, 7)
Co-ordinates of LA "B" C" under reflection in the origin :
A"= (-2, 3);B" = (-4,-4); C" = (-6,-7)
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| (b) | (4, 2) | Reflection in x-axis | ------- |
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