Cambridge IGCSE Mathematics · Syllabus 0580 · Algebra and Graphs
Introduction to Algebra
What is Introduction to Algebra?
The use of letters to stand for numbers, so that a relationship can be written down before the numbers are known. A letter may act as a specific unknown to be found, as a variable that ranges over many values, or as a generalised number in a rule true for all values. Substituting a number for a letter replaces the letter everywhere it appears, and a negative value must be enclosed in brackets so that powers and signs act on the whole value.
This definition is part of the Algebra and Graphs chapter in Cambridge IGCSE Mathematics.