With vertices A, B and C of ΔABC as centres, arcs are drawn with radii 14 cm and the three portions of the triangle so obtained are removed. Find the total area removed from the triangle.

figure.jpg

Slide64.JPG
Slide65.JPG

Go Ad-free

Transcript

Total area removed from the triangle = Area of sector at point A + Area of sector at point B + Area of sector at point C Area of Sector We know that Area of sector = šœƒ/(360Ā°) Ɨ Ļ€r2 and radius = 14 cm Thus, Area of Sector at point A = (āˆ š“)/(360Ā°) Ɨ Ļ€r2 Area of Sector at point B = (āˆ šµ)/(360Ā°) Ɨ Ļ€r2 Area of Sector at point C = (āˆ š¶)/(360Ā°) Ɨ Ļ€r2 Therefore, Total area removed from the triangle = (āˆ š“)/(360Ā°) Ɨ Ļ€r2 + (āˆ šµ)/(360Ā°) Ɨ Ļ€r2 + (āˆ š¶)/(360Ā°) Ɨ Ļ€r2 = šŸ/(šŸ‘šŸ”šŸŽĀ°) Ɨ Ļ€r2 (āˆ  A + āˆ  B + āˆ  C) Since sum of angles of a triangle = 180Ā° = 1/(360Ā°) Ɨ Ļ€r2 Ɨ 180Ā° = šŸ/šŸ Ɨ Ļ€r2 Putting r = 14cm = 1/2 Ɨ 22/7 Ɨ (14)2 = 11/7 Ɨ 14 Ɨ 14 = 11 Ɨ 28 = 308 怖š’„š’Žć€—^šŸ

Davneet Singh's photo - Co-founder, Teachoo

Made by

Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science and Computer Science at Teachoo