Understanding different types of angles and that angles in a triangle sum to 180° can be helpful when classifying a triangle. Recognising line symmetry and rotational symmetry will also help. Look for ...

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, right ...

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. What is a triangle? We all know that a triangle is a three-sided shape — 1, 2, 3 sides. A triangle also ...

An obtuse angle is between \(90^\circ\) and \(180^\circ\). To estimate the size of an angle, try thinking in terms of counting in quarter turns, or right angles. For example, the angle in the ...