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 ...

A scalene triangle with one angle greater than 90° is an obtuse-angled triangle. A scalene triangle with angles of 100°, 20° and 60° is an obtuse-angled triangle.