Question

The sum of the radii of two circle is 35cm and the difference of their areas is 770cmsquare what is their circumference?

Answer 1

Answer:

given,

    let r₁ be radius of 1 circle

        r₂ be radius of 2nd circle

              r₁ + r₂ = 35

             π r₁² - π r₂² = 770

            π( r₁² -r₂²) =770

            ( r₁ + r₂) (r₁ - r₂) = 770/22 * 7

                 35( r₁ - r₂) = 70* 7 /2

                    ( r₁- r₂) = 70 /35 *7/2

                    ( r₁- r₂) = 14/2

                      ( r₁- r₂) =7

  r₁+  r₂ = 35

   r₁-  r₂ =7

2r₁ = 42

r₁ = 21cm

r₂= 35 - 21

  = 14 cm

circumferance of 1 circle= 2π r₁

                                        = 132 cm

circumferance of 2nd circle= 2π r₂

                                             = 88 cm

hope it helps

plss mark as brainliest