Page 90 - Mathematics
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Opening the brackets gives,                        Solution

                 15z −  10 =  30                       Given  x =  4.
                        15z =  40                      Apply  the  definition  of  absolute
               Dividing by 15 on both sides of the     value. That is,
               equation gives,                                      ±  x =  4
                                                                          x
                              40                       Either,  x+ = 4 or − = 4
                          z =
                                   15                                Therefore,  x =  4 or x = − 4.
                              8
                            =
                                      3                Example 5.23
                             8
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               Therefore,  z =  .
                             3                         Solve for the value of x  if  6 x−  =  1.

               Example 5.21                            Solution
                                         8             Given  6 x−  =  1.
               Solve for the value of y, if   =  2.
                                       3y − 2          Apply  the  definition  of  absolute
               Solution                                value. That is,  ( 6 x±  −  ) 1=

               Given    8    =  2.                     Either,
                      3y − 2                           +  ( 6 x−  ) 1 or=  −  ( 6 x−  ) 1.=
               Multiplying by (3y − 2)  on both        It follows that,
               sides of the equation gives,                             6 x− = 1 or − 6 x+ =
                                                                                    1
                   8    ×  (3y −  2) =  2(3y −  2)                       x=  5 or x =  7
                (3y − 2)                               Therefore,  x=  5 or x = .
                                                                              7
                                           8 2(3y=  − 2)

                                           86y=  − 4   Example 5.24
                                         12 = 6y
                                   12                  Solve for the value of  x  if
                                          y =           x +  2 =  2  and represent the
                                    6
                                             =  2  2.  solution on a number line.
                            Therefore,  y =
    Mathematics Form One  Example 5.22     4.          Given  x + ±  ( x +  +  2 =  ) 2 =  ) 2 =  2. Apply the   ) 2 =  2.
                                                       Solution


                                                       definition of absolute value to get,
                                                                        2


               Find the values of  x if  x =
                                                                        2 or −
                                                                              ( x +
                                                       Either  ( x+


                                                  84




                                                                                        25/10/2024   09:51:27
   Mathematics form 1.indd   84                                                         25/10/2024   09:51:27
   Mathematics form 1.indd   84
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