standard_description: Classify two-dimensional figures based on the presence or absence of parallel or perpendicular lines, or the presence or absence of angles of a specified size. Recognize right triangles as a category, and identify right triangles.
problem_activity: Problem 1
Draw a right scalene triangle.
Problem 2
Draw an acute isosceles triangle.
Problem 3
True or false: all triangles have at least 2 acute angles.


aligns: yes