Triangles

Watch this lecture series, which discusses how to classify triangles by lengths of their sides and measures of their angles.

1. $\triangle L M N$ is an isosceles triangle and an acute triangle.

2. Lauren's triangle is an acute triangle and an isosceles triangle.

3. $\triangle G H I$ is an acute triangle and an isosceles triangle.

4. $\triangle N O P$ is an isosceles triangle and an obtuse triangle.