Question

A momento is made as shown in the figure. Its base PBCR is silver plated from the front side. Find the area which is silver plated.

Answer 1

Answer:

11.5 Square cm

Step-by-step explanation:

The memento is as shown in the attached picture.  

The angle at A for ΔABC is 90 degrees.  

Area of ΔABC = AB * AC/2 = 10* 10/2 = 50 Square cm.

Area of sector APR = Фπr²/360

Ф= angle in degrees.  

r = radius of circle = 7 cm.  

Area of sector APR = 90 * 22 * 7 * 7/(360 * 7) = 22 * 7/4 = 38.5 Square cm.  

Area of Silver coated base (PBCR) = Area of ΔABC – Area of Sector APR.  

= 50 – 38.5 = 11.5 Square cm.

Answer 2

Answer:

Step-by-step explanation:

From the given figure

Area of right-angled ΔABC

12

= # #10 10 = 50

Area of quadrant APR of the circle of radii 7 cm

14

= # #π ^ h7 2

.

14

7

22

= =# # 49 38 5 cm2

Area of base PBCR

= Area of ΔABC − Area of quadrant APR

= 50 38 5 11 5− . .=  cm2