A circle has a chord that goes from 3π2 to 7π4 radians on the circle. If the area of the circle is 121π, what is the length of the chord?

1 Answer
Mar 24, 2016

See geometric figure:
Chord, ¯¯¯¯¯¯AB=112

enter image source here

Explanation:

This straight forward problem:
A) Determiner the radius from CA=πR2; R=11
Look at the angular displacement between AB it form
a right angle at the center so trangle AOB is an "isosceles right angle". Thus the ratio of side of an isosceles right triangle is:
s1:s2:h=1:1:2 So for triangle AODa:f:¯¯¯¯¯¯AD=1:1:2
AD=1122, thus the chord, AB=112