if a wire is bent into the shape of a square , then the area of the square is 81cm square. when wire is bent into a semi circular shape, then the area of the semi-circle will be ?

• 77 cm^2
  Side of a square=Sqrt(81)=9, Perimeter of Square=4*9=36 cm.
  Perimeter of Square=Perimeter of Semi Circle
  36=[(2*Pi*r)/2]+2r=Pi*r+2r=r[(22/7)+2]=r*36/7 => r=7 cm.
  Area of Semi Circle=Pi*r^2/2=(22/7)*49/2=77 cm^2
  
• 11 years agoHelpfull: Yes(0) No(0)
• 162/pi equate the parameters.
• 11 years agoHelpfull: Yes(0) No(0)