Chapter 4 Activity 2
a. These four lines are not concurrent.
b. The circle passes through points B and C as well.
c. When the four lines are concurrent D is on the circle.
d. If the perpendicular bisectors of the sides of a quadrilateral are concurrent, then the quadrilateral is cyclic.
e. If a quadrilateral is cyclic then the four perpendicular bisectors of the sides are concurrent.