Equation vs. Expression

Date: 03/19/99 at 09:23:19
From: Jessica Sincebaugh
Subject: Algebraic Equation

I cannot find the definitions of a few terms. I think an algebraic 
equation is a statement with two related quantities. But how is it 
different from an algebraic expression? 

Thank You.

Date: 03/19/99 at 11:32:28
From: Doctor Jon
Subject: Re: Algebraic Equation & Surface Area

An algebraic expression is like a word, and an equation is like a 
sentence. For example 12c might represent a quantity of eggs. If c is 
the number of cartons of eggs, and there are 12 eggs in each carton, 
you can see that 12c is a useful way of expressing the total quantity 
of eggs. 

If you have another number or expression, you can relate them in an 
equation. For example, let 12c = 60. This is an algebraic equation with 
one variable. Solving this kind of equation reveals c = 5. Thus we have 
five cartons. 

Note the distinction of having 12c by itself (an expression) and relating 
it to another number using an equals sign: 12c = 60 (an equation).  

For a more precise definition, see if your textbook has a glossary, or 
index, or a table of contents. By looking up your words in any or all 
of these parts of your text, you should be able to find the kind of 
definition that your teacher is looking for.

- Doctor Jon, The Math Forum
  http://mathforum.org/dr.math/