CENTUM

https://drive.google.com/file/d/1FKS2dkoYioMq37BQB6-thQRrjxyirsQ-/view?usp=sharing

radius of semi circle = 21cm

area of semi circle = pi*r^2/2

=>22/7*21*21/2

=>11*3*21=693

A-B=357

x+B=693

A+x=1050

A+x=area of triangle

area of triangle = 1/2*base*height

=>1050=1/2*base*height

=>1050/21=base

QR=50

https://drive.google.com/file/d/15-2He-N92RpqAgLjZL6O6infKg7QDsQe/view?usp=sharing

https://npsedu-my.sharepoint.com/:b:/g/personal/harshith106333_npsrnr_com/EUIWBcSZNBBIpHapPWmyMDYBZ-HU5LfT2_8uH6u_OaRE6Q?e=8QLnLu

Area of semi circle = 1/2 * 22/7 * 21^2 = 693 cm^2

Ar of PQR = 693 + (a-b) = 693 + 357

= 1050cm^2

And Ar of PQR = 1/2.b.h = 1050

therefore, 1/2 * b * 42 = 1050

b = 1050/21

hence base (QR) = 50cm

Anirudh Seetharaman’s answer:

https://drive.google.com/file/d/1e9iZlDvK9rp5WqPCiEUDQ-E4y9tWsh–/view?usp=sharing

Jahaan Kukreja’s answer:

https://drive.google.com/file/d/19N8_z4bs_ngVANAZUcd90DYfl2y8vWhW/view?usp=sharing

https://drive.google.com/file/d/1dohentOfgYxZH9WdPrywEfjo1aY1PRjn/view?usp=sharing