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**Choose the correct alternative:**

In ∆ABC, AB = `6sqrt(3)` cm, AC = 12 cm, and BC = 6 cm, then m∠A = ?

#### Options

30°

60°

90°

45°

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#### Solution

**30°**

We know that, 6 = `1/2`(12) and

`6sqrt3 = sqrt3/2 (12)`

∴ BC = `1/2 "AC and AB" = sqrt3/2 "AC"`

∴ ∠A = 30° ...(Converse of 30°-60°-90° theorem)

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