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**Choose the correct alternative:**

A rectangle having length of a side is 12 and length of diagonal is 20, then what is length of other side?

#### Options

2

13

5

16

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#### Solution

**16**

Let ABCD be the given rectangle.

AC = 20 units and BC = 12 units

In ∆ABC,

∠B = 90°

∴ AC^{2} = AB^{2} + BC^{2 } ...[Pythagoras theorem]

∴ 20^{2} = AB^{2} + 12^{2}

∴ 400 = AB^{2} + 144

∴ AB^{2} = 256

∴ AB = 16 units

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