Terms are the different parts of an expression. A term can be a simple number, a variable (letter), or a combination of a number and letters. For example, 25, 6g, 7h and 17bc are all terms.
A taxi company charges for fares at a rate of £2.50 plus £1.05 per kilometre. This can be written as an expression:
Fare in £ = 2.50 + 1.05k, where k is the number of kilometres driven.
The 2.50 and 1.05 numbers cannot be added together, because the value of 1.05k changes depending on how many kilometres are driven.
In an expression 3 + 2x + 7x2 + 4y, the 3, 2x, 7x2 and 4y are all separate terms. If the letters are different, or have different powers, they are different terms: x, x2 and x3 are all different terms.
Terms that can be added together are called like terms. Terms that cannot be added together are called unlike terms.
1. How many terms are there in this expression: 3 + 2a + 8b + 4c(.
There are four terms: the 3 is a term (as it is a number), and each combination of number-letter is also a term.
2. Is 2n + 4 an expression or a term?
Answer: It is an expression, as it consists of more than one term.