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Example 5.41                                            5
                                                                  x ≤
                                                                           8
              Solve for the value of x  if 5x +> 1.                   5
                                           2
                                                        Therefore,  x ≤  .
              Solution                                                8
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              Given 5x +>    1.                         Example 5.43                             Tanzania Institute of Education
                          2
              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
                           x >−                         Opening brackets and simplifying
                                     5                  gives,
                               1
              Therefore,  x >−  .                       2x +  10 5x≤  +  1
                               5
                                                        Collecting like terms gives,
              Example 5.42
                                                                 1 10
                                                        2x − 5x ≤−
                                                               − 3x ≤− 9
              Find the value of x which satisfy the
                                   1                    Divide by  3−  on both sides of the
                               3
              inequality  –4x +≥    .
                                   2                    inequality to get,  x ≥ 3.
              Solution                                  Therefore,  x ≥  3.
                               1
                           3
              Given  –4x +≥    2 .                      Example 5.44
              Subtracting 3 from both sides of the
                                                                                    2
              inequality to obtain,                     Indicate the solution of  x ≤ on a
                               1                        number line.
                        3 3
                  –4x +− ≥       − 3
                               2                        Solution
                                 5
                         –4x ≥−                         Given  x ≤  2,  it implies that
                                 2                      ± x ≤  2
              Divide by  4−  on both sides of the       Thus, either  x+ ≤  2 or − ≤  2.           Mathematics Form One
                                                                                x
              inequality to get,

                                                                x ≤ 2 or x ≥− 2




                                                 103




                                                                                        25/09/2025   15:01:19
   Mathematics form 1.indd   103                                                        25/09/2025   15:01:19
   Mathematics form 1.indd   103
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