Variable.
A variable is any letter that stands for a number. The most commonly used letters are x and y, but you can
use any letter.
Constant.
A constant is a number without a variable. For example: The equation 6m + 7 = –m has one constant, the number 7.
Equation.
An equation is any string of numbers and symbols that makes sense and includes an equal sign. For example, here are three equations:
A variable is any letter that stands for a number. The most commonly used letters are x and y, but you can
use any letter.
Constant.
A constant is a number without a variable. For example: The equation 6m + 7 = –m has one constant, the number 7.
Equation.
An equation is any string of numbers and symbols that makes sense and includes an equal sign. For example, here are three equations:
Expression.
An expression is any string of numbers and symbols that makes sense when placed on one side of an equation. For example, here are four expressions:
An expression is any string of numbers and symbols that makes sense when placed on one side of an equation. For example, here are four expressions:
Term.
A term is any part of an expression that’s separated from the other parts by either a plus sign (+) or a minus sign (–). Important: A term always includes the sign that immediately precedes it. For example,
The expression 3x – 7 has two terms: 3x and –7.
The expression –x2 – 9x + 11 has three terms: –x2, –9x, and 11.
The following expression
A term is any part of an expression that’s separated from the other parts by either a plus sign (+) or a minus sign (–). Important: A term always includes the sign that immediately precedes it. For example,
The expression 3x – 7 has two terms: 3x and –7.
The expression –x2 – 9x + 11 has three terms: –x2, –9x, and 11.
The following expression
has one term:
Coefficient.
A coefficient is the numerical part of a term, including the sign that precedes it (+ or –).
Important:
Every term has a coefficient. When a term appears to have no coefficient, its coefficient is either 1 or –1, depending on the sign. For example,
The term 3x has a coefficient of 3.
The term –9x has a coefficient of –9.
The term –x2 has a coefficient of –1.
Absolute Values.