Question

in agiven figure OACB is quadrant of acircle with centre O And radius 3.5 if OD=2cm find the area of shaded region

Answer 1

Area of equilateral triangle



Share



Radius of circle = 100 cm (half of a)

Area of circle = πr2 = π x 1002 = 31400 sq cm

Area of three sectors = ½ Area of circle (Because all angles sum up to 180)

= ½ x 31400 = 15700 sq cm

So, area of shaded portion = 17302.5 – 15700 = 1602.5 sq cm

Answer 2

$\huge{\underline{\bigstar{\sf{solution!!}}}}$

Given,OACB is a quadrant of a circle

Radius = 3.5 =7/2 cm; OD= 2cm

$\large{\sf{area\: of \: the \: shaded \: region = area \: of \: a \: quadrant \: cricle - area \:of \: triangle \:BOB}}$

=1/4πr²-1/2×b×h

=1/4×22/7×7/2×7/2-1/2×7/2×2

=11×7/2×2×2 -7/2

[=77/8-7/2

=9.625-3.5

$\large{\boxed{\sf{=6.125cm2}}}$

━━━━━━━━━━━━━━━━━━━━