Discusses the properties and types of triangles, explaining that a triangle is a closed figure with three sides and angles. It categorizes triangles into equilateral, isosceles, scalene, obtuse ...

The three doweled pieces of this unpainted wooden model can be arranged either as a rectangle or as an obtuse-angled triangle. Compare models 1985.0112.190 through 1985.0112.202. For further ...

An obtuse-angled triangle is a triangle that has one obtuse angle. Acute-angled triangle. In an acute-angled triangle, all three angles are acute. SUBJECTS: Maths. YEARS: 5–6, 7–8.