Question

. The area of the ring between two concentric circles is 3168 cm2. Find the radii of the two
circles if (i) their sum is 42 cm and (ii) their difference is 28 cm.​

Answer 1

Step-by-step explanation:

Let two radius are 'x' and 'y', so,

x+y=42....(1)

and

x−y=28.....(2)

Now adding (1) and (2), we get

2x=70

x=35

Putting in (1)

35+y=42

y=7

Therefore, radius of two concentric circles are 35 cm and 7 cm.