We cannot take half of 9 people. The even numbers, then, are the numbers divisible by 2: 2, 4, 6, 8, and so on. The odd numbers are 1, 3, 5, 7, and so on. If you do not know half of some even number, you can find it by decomposing it mentally into two even numbers whose half you do know.
To draw a shape, line or angle accurately using a compass and straightedge (ruler). Sometimes you are also allowed to use a protractor and triangle.
LINK / CITE ADD TO WORD LIST. noun. The definition of geometry is a branch of math that focuses on the measurement and relationship of lines, angles, surfaces, solids and points. An example of geometry is the calculation of a triangle's angles.