For any triangle you can construct a line through one of the vertices parallel to the opposite edge.
Using what you know about angles and parallel lines prove that the angles of the triangle add up to 180 degrees.
Click here to download the ANGLE SUM worksheet.
Click here to download the ANGLE SUM Guide for Parents.
Click here for the Notes for Teachers.
You must be logged in to post a comment.
Here is the official website for COVID-19 updates.