SOLUTION: an opened cone with a base radius 28cm and perpendicular height 96cm was stretched to form a sector of a circle.calculate the area of the sector

Algebra ->  Surface-area -> SOLUTION: an opened cone with a base radius 28cm and perpendicular height 96cm was stretched to form a sector of a circle.calculate the area of the sector      Log On


   

Question 1090661: an opened cone with a base radius 28cm and perpendicular height 96cm was stretched to form a sector of a circle.calculate the area of the sector
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
r, radius of the unfolded cone sector

r%5E2=28%5E2%2B96%5E2
r%5E2=10000
r=100

circumference of the cone was 2pi%2A28=56pi.

Unfolded cone, now the sector of a circle, has arc of 56pi.
Circumference of the entire circle would be 2%2Api%2A100.

Area of the sector: %28%2856pi%29%2F%282%2Api%2A100%29%29pi%2A100%5E2-----simplify this.