Question

find the length of a quadrant arc of the circle having radius of 28cm​

Answer 1

[tex][/tex]

Answer

In △ BAC, by pythagoras theorem,

BC

2

=AB

2

+AC

2

BC

2

=784+784

BC=28

2

cm

2

BC

=14

2

cm

Now,

A=ar(BDCEB)

A=ar(BCEB)−ar(BCDB)

A=ar(BCEB)−[ar(BACDB)−ar(BAC)]

A=[

2

1

(

7

22

×(14

2

)

2

)−(

4

1

×

7

22

×28

2

−

2

1

×28×28)]

A=[

2

1

×

7

22

×196×2−

4

1

×

7

22

×28×28+

2

1

×28×28]

A=616−616+392=392 cm

2