This task was first used with a class who had been working on right angled trig, but hadn’t done anything in context yet.  It was used as a task to focus on mathematical thinking and problem solving skills.  If pupils have never solved a problem involving an isosceles triangle using trig then this task can be used to make significant steps in their understanding.  

The framework this particular class have developed together is (in no particular order of doing): 

1.  Make a sketch
2.  Fill in anything we know, or that we can work out easily.
3.  Mark in what we want to know
4.  Write down any formulas that might be useful. 
5.  Consider making a simpler sketch

All of these strategies can be utilised in this task. 

Some possible task stems:

• Find the missing sides and angles of this triangle
• Or less leading would be…  Find the perimeter of the triangle
• Find the area of the triangle
• Or simply, find everything that you can about this triangle