Page 1 :
VIVEKANANDA RESIDENTIAL SCHOOL, , Class-VII Subject: MATHEMATICS, Chapter-4, SIMPLE EQUATIONS, NOTE: Note down the Key points and exercise problems neatly, in your Math Notebook., , , , , , Variable:, , Variable is an unknown number which could have a different numerical value., It is called Variable as it can vary. It is represented by different letters like x, y,, a, b ete., , Constant:, , Constant is a fixed value like 5, 0 2 etc, , Algebraic Expressions, , It is an expression involving constant, variable and some operations like, addition, multiplication etc., , Example: 6x - 3 is an expression in variable x., , Equation, , An equation is a condition on a variable. It says that two expressions are equal., , coefficient variable constant, wi / Z N, S5x+7=/2, ates, expression enpetenion, equltion, , Terms: Sx, 7, V2, , The condition is that two expressions should have equal value., The value of the variable in an equation for which the equation is satisfied is, called the solution of the equation., , Example: The solution for the equation 2x-3=5 is