Page 58 - Year 10 Knowledge Organiser
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Maths: FOUNDATION: : Algebra: 1 of 4



       Simplifying expressions                             Substitution                                        Expressions as functions
       You can simplify by:                                To  substitute  means  to  replace  a  letter  for  a
       Collecting like terms: Like terms are those with    number.                                             Expressions  can  be  written  as  simple  function
       the same letter and power.                                                                              machines.


                                                           4b = 4 x 3 = 12                                     E.g.


                                                           7b – 3c = (7 x 3) – (3 x (-5)) = 21-(-15)= 36       3n+4 means multiply n by 3 then add 4





                                                                                                               If the input was 2, the output would be
       Using laws of indices                               Expanding brackets                                  (3 x 2) + 4 = 10
       Start by writing out in full:
             3                   4                         Multiply the term outside the bracket with each     If  the  output  was  25,  we  would  be  able  to  use
                =      ×      ×             =      ×      ×      ×       term inside the bracket.
            3    4                                  7                                                          inverse  functions  to  work  out  what  the  input
       So      ×      =      ×      ×      ×      ×      ×      ×      =     
       To  multiply two  terms  with  the  same  base  you                                                     would have been.
       can add the powers.


                5
                          ×      ×      ×      ×       2
                  =                        =     
                   3           ×      ×     
       To divide two terms with the same base you can
       subtract the powers.                                Factorising                                         Using algebra to solve problems

       If  you  need  to  multiply  a  combination  of     To factorise means to put into brackets.            We  can  use  expressions  to  work  out
       numbers  and  powers,  work  with  the  numbers                                                         different values for real life problems.
       separately first:                                   Find the highest common factor for both terms       E.g.
                                                           (this might be a letter or a number or both)        The amount of medicine (m) in ml needed is two

                                        
                                             
                   
                         
                     ×          =      ×      ×      ×      =                                                  times the weight in kg, divided by 10. Work out
                                                                                                               the amount of medicine for a 15kg child.
                    4 2
                                4
                                      4
                  (     )                            ×      =      8                                                                m=  2    
       If you have a power raised to a power, you can                                                                               2×15
                                                                                                                                       10
       multiply the powers                                                                                     so for this child m =  10  = 30 ÷ 10 = 3        .
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