Page 259 - ICSE Math 6
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Terms  A constant/a variable/a combination of constants and variables


                                             Like terms  Terms with the same literal factors  2x, –11x and 230x


                                             Unlike terms  Terms with different literal factors  5y, –11m and pq

                                             Constant terms  A term with no variable  –7, 21, 315 and so on.




                                                 In a term, constant is known as the numerical factor.
                                     Numerical                                                  Literal
                                       Factor                                                   Factor
                                                 In a term, variables are known as the literal factors.



                                 Algebraic Expressions                       Monomial: With one non-zero term.
                                                           With powers
                               A collection of one or more   of variables in   Binomial: With two non-zero terms.
                               terms combined together by   whole numbers    Trinomial: With three non-zero terms.
                                 addition or subtraction.                    Polynomial: With finite non-zero terms.


                    OPERATIONS ON ALGEBRAIC EXPRESSIONS

                                                      Substitution               Example
                                                 The method of finding the    For x = 2,
                                                 value of an expression by
                                                substituting the values of the   2x + 1 = 2(2) + 1
                                                 variables in the expression.      = 1

                                  Removing a Bracket

                                 When there is a ‘+’ sign   Remove the bracket and retain the signs of each term inside
                                 before the bracket.        the bracket as it is. For e.g.: 3 + (x + 2y – 7) = 3 + x + 2y + 7
                                 When  there is a ‘–’ sign   Remove the bracket and change the signs of each term inside
                                 before the bracket.        the bracket. For e.g.: 3 – (x + 2y – 7) = 3 – x – 2y + 7


                    LINEAR EQUATIONS IN ONE VARIABLE


                                    Equation    A mathematical statement which shows the equality of two expressions.


                                    Linear Equation   An equation which consists of variables with highest power 1.

                                    Linear Equation in One Variable  A linear equation with only one variable.


                                   x = y                   x = y                     Solution of a Linear Equation
                            ⇒  x + a = y + a         ⇒ x – a =  y – a
                                          Properties of                                  Value of variable which
                                           an Equation                                 satisfies the given equation.
                                   x = y             x = y and a ≠ 0
                            ⇒  x × a = y × a         ⇒ x ÷ a =  y ÷ a


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