Showing posts with label triangle properties. Show all posts
Showing posts with label triangle properties. Show all posts

Saturday, August 23, 2008

Solving triangles decision tree

Before entering declination and inclination in year 10 I wanted my students to really consolidate how to solve a variety of triangles.

I set up a decision tree on the whiteboard splitting the various methods for solving triangles.
My students are heavily reliant on notes to solve problems but now can see which parts of their notes to use for a variety of problems. They are even labelling triangles correctly!

Obviously the tree has limitations - finding third angles when two angles are given, finding the unknown angle with the cosine rule (when not the central angle) and the "ambiguous angle" with the sine rule.

Another area I have focussed on is providing differentiation for students of varying levels of algebraic skill. For some I have written all variations of the various rules on their notes page and ensured they can find the correct rule and use correct mathematical notation when recording their logic for solving a problem. For more capable students I have suggested only the bare minimum in their notes and encouraged them to identify the subject and manipuate equations to suit (as it is great practice). Some students have worked more on mastering sine & cosine rules, others have experimented with 3D trigonometry.

After discussing the limitations and completing a number of examples, suddenly the lights turned on for many of my students.. for the first time in a while I felt they were ready to move on. This is my cue to run a revision session of mixed and composite examples and check for further issues.