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AD is a diameter of a circle and AB is a chord If AD = 30 cm and AB = 24 cm then the distance of AB from the centre of the circle is

#### Options

10 cm

9 cm

8 cm

6 cm

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#### Solution

**9 cm**

**Explanation;**

Hint:

In ΔAOC,

AO = 15 cm

AC = `1/2` AB

= `1/2 xx 24`

= 12 cm

In ΔAOC,

OC^{2} = AO^{2} – AC^{2}

= 15^{2} – 12^{2}

= 225 – 144

= 81

OC = `sqrt(81)`

= 9 cm

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