Different types of triangles

This morning in room 8 for maths we investigated the angles of triangles.Firstly I drew a equilateral triangle on a piece of paper,then cut out each side of the triangle and put them together in a pattern  to make a straight line with no gaps in between.I learn't that each triangle is a straight line because it is always one hundred and eighty degrees.We tried the same technique with the isosceles triangle,and resulted in the same angles one hundred and eighty degrees which means that all triangles are straight angles.