Ncert class 8 maths chapter 2 deals with  Linear equation in one variable

Introduction: Variable : A symbol which can takes various numerical values is called variable.

Ex : x,y…

Term : A Constant alone or A variable alone or combination of constant and variable with multiplication ‘×’ , division  ‘÷’ is called term.

Multiplication ‘×’ ,division  ‘÷’ do not separate the terms.

Ex: x/2y, xy  are single terms.

Expression : An expression is a single term or a combination of terms connected by the symbols ‘+’(plus) or ‘-‘ (minus).

Ex : x²+y is an expression having two terms.

x+y²+z is an expression having 3 terms.

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