Question

7. Find the area of shaded portion​

Answer 1

=>Let the radius of smaller circle be r and bigger circle be R cm

• Radius of bigger circle = 21+3.5 cm

= 24.5 cm

So,

Area of smaller circle = r²

= 3.14*21*21 cm²

= 1384.74 cm²

Area of bigger circle = R²

= 3.14*24.5*24.5 cm²

= 1884.78 cm²

Area of shaded portion = 1884.78-1384.74 cm²

= 500.04 cm²

Answer 2

Answer:

The first term is, x2 its coefficient is 1 .

The middle term is, -9x its coefficient is -9 .

The last term, "the constant", is -5

Step-1 : Multiply the coefficient of the first term by the constant 1 • -5 = -5

Step-2 : Find two factors of -5 whose sum equals the coefficient of the middle term, which is -9 .

-5 + 1 = -4

-1 + 5 = 4

Observation : No two such factors can be found !!