Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. What is a quadrilateral? A quadrilateral is a four-sided shape where each of the sides are straight and ...

The total area of a compound shape is found by adding up the areas of the rectangles that have created the whole shape. This may be done in more than one way. The calculation may use a subtraction of ...

A square has four right angles (90°). Each diagonal splits a corner into two angles of 45°. Note also that the diagonals cut each other in half at right angles. A rectangle has four right angles. The ...