Question 5 - Figure it out - Page 20, 21 - Chapter 1 Class 7 - Geometric Twins (Ganita Prakash II)

Transcript

Question 5 Find ∠B and ∠C, if A is the centre of the circle.If A is center of circle AB & AC will be radius ∴ AB = AC = Radius Thus, ∆ ABC is an isosceles triangle We know that Angles opposite equal sides are equal Therefore, ∠ C = ∠ B Now, in ∆ ABC By Angle Sum Property of Triangle ∠ A + ∠ B + ∠ C = 180° Putting ∠ A = 120° 120° + ∠ B + ∠ C = 180° Putting ∠ B = ∠ C 120° + ∠ B + ∠ B = 180° 120° + 2 × ∠ B = 180° 2 × ∠ B = 180° – 120° 2 × ∠ B = 60° ∠ B = (60°)/2 ∠ B = 30° Thus, ∠ B = ∠ C = 30°