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Question
- The point P (2, –4) is reflected about the line x = 0 to get the image Q. Find the co-ordinates of Q.
- The point Q is reflected about the line y = 0 to get the image R. Find the co-ordinates of R.
- Name the figure PQR.
- Find the area of figure PQR.
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Solution
i. P(2, –4) is reflected in (x = 0) y-axis to get Q.
\[\ce{P(2, -4) ->[My]Q(-2, -4)}\]
ii. Q(–2, –4) is reflected in (y = 0) x-axis to get R.
\[\ce{Q(-2, -4) ->[Mx]R(-2, 4)}\]
iii. The figure PQR is right angled triangle.
iv. Area of ΔPQR = `1/2 xx PQ xx QR`
= `1/2 xx 4 xx 8`
= 16 sq. units
RELATED QUESTIONS
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Use graph paper for this question.
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Use a graph paper for this question.
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- Write the equation of the line L1 and L2.
- Write down the images of points P(3, 4) and Q(−5, −2) on reflection in L1. Name the images as P' and Q' respectively.
- Write down the images of P and Q on reflection in L2. Name the image as P'' and Q'' respectively.
