Page 109 - Mathematics
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Example 5.42                                            5
                                                                  x ≤
                                                                           8
                                           2
              Solve for the value of x  if 5x +> 1.                   5
                                                        Therefore,  x ≤  .
              Solution                                                8

                          2
              Given 5x +>    1.                         Example 5.44                             Tanzania Institute of Education
              Subtract 2 from both sides of the
              inequality. That is,                      Solve the inequality

                      5x + 2 2 12− >−                   5(x + 2) 3x−  ≤ 4 2x+  + 3(x − 1).
                                 5x >− 1
              Divide by 5 on both sides                 Solution
                          5x  >− 1                      Given
                                   5  5                 5(x + 2) 3x−  ≤  4 2x+  + 3(x − 1).

                                 1                      Opening brackets and simplifying
                           x >−
                                     5                  gives,
                               1
              Therefore,  x >−  .                       2x +  10 5x≤  +  1
                               5
                                                        Collecting like terms gives,
              Example 5.43                              2x − 5x ≤−
                                                                 1 10
                                                               − 3x ≤− 9
              Find the value of x which satisfy the     Divide by  3−  on both sides of the
                                   1
                               3
              inequality  –4x +≥    .                   inequality to get,
                                   2
                                                        x ≥ 3
              Solution                                  Therefore,  x ≥  3
                               1
                           3
              Given  –4x +≥    2 .
              Subtracting 3 from both sides of the      Example 5.45
              inequality to obtain,
                                                                                    2
                               1                        Indicate the solution of  x ≤ on a
                        3 3
                  –4x +− ≥       − 3                    number line.
                               2
                                 5                      Solution
                         –4x ≥−
                                 2                      Given  x ≤  2,  it implies that
              Divide by  4−  on both sides of the       ± x ≤  2                                   Mathematics Form One
              inequality to get,                        Thus, either  x+ ≤  2 or − ≤  2.
                                                                                x

                                                                x ≤ 2 or x ≥− 2



                                                 103




                                                                                        25/10/2024   09:51:37
   Mathematics form 1.indd   103                                                        25/10/2024   09:51:37
   Mathematics form 1.indd   103
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