|Class 7 Maths Algebraic Expressions||Terms of an Expression|
Terms of an Expression
Terms are added to form an expression.
Ex: terms 3x and 7 are added to form the expression 3x + 7
Again, the expression 2y2 – 7xy are formed by adding the terms
2y2 and -7xy i.e. 2y2 + (-7xy) = 2y2 – 7xy
Factors of a term
A term is a product of its factors.
Let us take a term 2y2
The term 2y2 is a product of 2, y and y. Now, we say that 2, y and y are the factors of the term 2y2
Again the term – 7xy is a product of the factors -7, x and y.
The numerical factor is said to be the numerical coefficient or simply the coefficient of the term.
Ex: In the term 20y2, 20 is the coefficient of y2.
Again, in the term -3xyz, -3 is the coefficient of xyz.
In general, a coefficient may be either a numerical factor or an algebraic factor or a product of two or
Ex: In the term 7xy, 7 is the coefficient of xy, x is the coefficient of 7y and y is the coefficient of 7x.
In 5xy2, 5 is the coefficient of xy2, x is the coefficient of 5y2 and y2 is the coefficient of 5x.
We can represent the terms and factors of an expression in an efficient way by using a tree diagram.
Ex: Let us take the expressions 3xy – 10x, 5x3 – 2xy to draw the tree.
Problem: Identify terms which contain x and give the coefficient of x.
(i) y2 x + y (ii) 13y2 – 8xy (iii) x + y + 2 (iv) 5 + z + zx (v) 1 + x + xy
(vi) 12xy2 + 25 (vii) 7x + xy2