median
don steward
mathematics teaching 10 ~ 16

Sunday, 27 October 2013

angle bisectors

an intention of this task is that students utilise an angle bisecting skill to establish and then possibly prove a relationship between two angles




















there is a geogebra applet at NRICH that enables later work to focus on reasons for the relationship between these angles

other questions might occur:
e.g.
  • what is the condition (in the applet) for CE being parallel to BA?
  • can angle BAC ever be 90 degrees?
  • what happens if the original triangle is equilateral?

No comments: