The geometric mean of two positive numbers a and b is .
A sequence of numbers where the first one is repeatedly multiplied by a fixed number to obtain the following numbers of the sequence. the fixed number is acalled the common ratio.
A composite transformation where a figure is reflected and then translated.
A rectangle where the ratio of its length to its width is .
See Sphere.
Is the largest common factor betwen two or more numbers, that is the largest numbers that divides all the given numbers.
A tessellation of congruent squares used in coordinate systems or to measure distances, areas, etc.