This is an activity that students can work on individually or in small groups.
They are given twelve cards. Each card has a triangle on it with a piece of information that must be found (a side or an angle). The students are to place each card into one of the following categories based on how the missing information would be found:
180 degrees in a triangle
Cannot be done!
When I use this activity I check that the students have correctly organized the cards before they proceed to solve the problems that can be solved.
The cards can be printed and cut out in advance and given to students in an envelope. Or, the 12 cards are provided in a random order so that the students can cut them out to save you time!
You can have the students hand in their answers for you to assess.
Solutions are also provided.