#4044. variable

Mathematics, level: Elementary
Posted Tue Sep 25 19:03:48 PDT 2007 by Minnu (Minnu101@aol.com).
variable
Edison elementry, Morton Grove,US
Materials Required: paper,pen, notebook
Activity Time: addition
Concepts Taught: variable

variable you can change numbers. and for this reason i will give an example,
2

x

3 + 7

2 × y + 5

A variable is a symbol that represents a number. Usually we use letters such as n, t, or x for variables. For example, we might say that s stands for the side-length of a square. We now treat s as if it were a number we could use. The perimeter of the square is given by 4 × s. The area of the square is given by s × s. When working with variables, it can be helpful to use a letter that will remind you of what the variable stands for: let n be the number of people in a movie theater; let t be the time it takes to travel somewhere; let d be the distance from my house to the park.

2 + 6 × (4 - 2)

z + 3 × (8 - z)