Question

Tick the correct answer and justify: In ΔABC, AB = `6sqrt3` cm, AC = 12 cm and BC = 6 cm.

The angle B is:

Options

• 120°

• 60°

• 90°

• 45°

Answer 1

Given that, AB = `6sqrt3` cm, AC = 12 cm, and BC = 6 cm

It can be observed that

AB² = 108

AC² = 144

And, BC² = 36

AB² +BC² = AC²

The given triangle, ΔABC, is satisfying Pythagoras theorem.

Therefore, the triangle is a right triangle, right-angled at B.

∴ ∠B = 90°

Hence, the correct answer is 90°.