Question

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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

Answer 1

16

Let ABCD be the given rectangle.

AC = 20 units and BC = 12 units

In ∆ABC,

∠B = 90°

∴ AC² = AB² + BC²      ...[Pythagoras theorem]

∴ 20² = AB² + 12²

∴ 400 = AB² + 144

∴ AB² = 256

∴ AB = 16 units