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Question
Using a graph paper, plot the point A (6, 4) and B (0, 4).
(a) Reflect A and B in the origin to get the image A’ and B’.
(b) Write the co-ordinates of A’ and B’.
(c) Sate the geometrical name for the figure ABA’B’.
(d) Find its perimeter.
Solution
(a)
(b) Co-ordinates of A'=(-6,-4)
Co-ordinates of B'=(0,-4)
(c) ABA'B' is parallelogram.
(d) In ABA'B',BB'=8 units, A'B'=6 units
`therefore BA'=sqrt(6^2+8^2)=sqrt(36+64)=sqrt100=10 `units
`=>B'A=10 ` units
AB=A'B'=6units
∴ the perimeter of ABA'B'=AB+BA'+A'B'+B'A
=6+10+6+10
=32 units
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