Definition

A constant is any number or figure, ex: 1, 2, ½, -6, 20, etc...

A variable is a letter written to represent any number, ex: a, b, c, d, etc…

A coefficient is any number written in front of a letter (variable), ex: in 3x, 3 is the coefficient of x. In ¾x, ¾ is the coefficient of x.

An algebraic expression is a combination of variables and constants using the basic arithmetic operations, ex: 2x + 3y, 2a + b.

In an algebraic expression, each constant or variable at a combination by operation + or – is called a term. Therefore, the expression x – 3y – 2z – 8 has four terms (x, 3y, 2z and 8).

Ex: 1) name the variables, constants and terms in the following expressions

a) 4a + 3b – 7, b) 2x – 3y + 6

2) what is the coefficient of the variables in question 1 above

Solution:

1) a) variables = a and b, constant = 7, 3terms = 4a, 3b, 7     b) variables = x and y, constant = 6, 3terms = 2x, 3y, 6

2) Numerical coefficient of a = 4 and b = 3, numerical coefficient of x = 2 and y = -3