Question

ABCD is a rectangle in which AB=20cm and BC=10cm. A semicircle is drawn with centre O and radius 10root2. cm. It passes through A and ,touching the ends. Find the area of shaded region .

Answer 1

here what is the shaded region

if it is the whole figure then it is

ar of rectangle + the ar of semicircle

if it is only to find the semicircle

ar of rectangle - ar of semicircle

Answer 2

Answer:

Step-by-step explanation:

In triangle AOB

AB = 20cm

AB² = 400cm²

AO = 10√2 cm

AO² = 200cm² = BO²

So AB² = AO²+ BO²

So AOB is a right angle (converse of Pythagoras theorem)

AOB is a quadrant of circle.

So find the area of segment of the circle

And so subtract it from area of rectangle

You will get your answer as 143cm²