Question

Solution

Correct option is

2

Let A (0, 0), B (2a, 0), C (a, 2r), D (0, 2r). Since the circle touches the parallel sides AB and CD its diameter is 2r so that the radius of the circle is r. Since it touches AD, distance of the centre from AB and AD is r and the coordinates of the centre are (rr). or         2rx + ay – 4ar = 0

As the circle touches BC, distance of the centre from BC is also r.     From (1) and (2) we get a = 3, r = 2

So the required radius is 2. SIMILAR QUESTIONS

Q1

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x2 + y2 – 4x + 2y + 4 = 0 orthogonally, is

Q2

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Q3

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Q4

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Q5

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Q6

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Q7

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Q8

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Q9

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Q10

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