Question

in ∆ABC,AB= 6√3 cm,AC=12 cm, BC 6 cm, find measure of < A.

Answer 1

Step-by-step explanation:

As,

(6√3)2 + 62 = 122

⇒ AB2 + BC2 = AC2

i.e. sides of the triangle ABC satisfy the Pythagoras theorem

(Hypotenuse)2 = (base)2 + (Perpendicular)2

∴ ABC is a right-angled triangle with hypotenuse as AC

Now,

BC =1/2 AC

By converse of 30°-60°-90° triangle theorem i.e.

In a right-angled triangle, if one side is half of the hypotenuse then the angle

opposite to that side is 30°.

∠A = 30°.