A semicircle is drawn with AB as its diameter .From c. apont on AB,a line perpendicular to Ab is drawn meeting the circumference of the semicircle at D.Given that AC=2 cm and CD=6 cm.area of the semicircle (in sq.cm)will be .

a)82pi b)55pi c)31pi d)50pi

• 1. draw a semicirle with dia AB
  2. draw perpendiculr CD
  3. join D with O (mid point of semicirle)
  let radius be x; AO=DO=X
  now in triangle CDO
  CD^2+CO^2=DO^2
  6^2+(X-2)^2=X^2
  On solving we get x=10
  so area of semicircle becomes 100pi/2=50pi
  
  
• 8 years agoHelpfull: Yes(15) No(1)
• radius=10
  area of semicircle=50pi
• 8 years agoHelpfull: Yes(0) No(2)
• 6^2+ (r-2)^2 = r^2
  => r=10
  area=pi.r^2/2
  => 50pi
• 8 years agoHelpfull: Yes(0) No(4)
• ans is 31pi
  
• 8 years agoHelpfull: Yes(0) No(9)