a) [tex] \frac{60}{100} \times( 2a + 6) = \frac{80}{100} \times (3a - 6)[/tex]
=> [tex] \frac{3}{5} \times (2a + 6) = \frac{4}{5} \times (3a - 6)[/tex]
=> [tex] \frac{6a}{5} + \frac{18}{5} = \frac{12a}{5} - \frac{24}{5} [/tex]
=> [tex]6a + 18 = 12a - 24[/tex]
=> [tex]6a = 42[/tex]
=>[tex]a = 7[/tex]
b) |1-2x| ≤ a
=> |1-2x| ≤ 7
=> -7 ≤ 1-2x ≤ 7 |-1
=> -8 ≤ -2x ≤6 |: (-2)
=> 4 ≥ x ≥ -3
dar x ∈ Z => x ∈ {-3, -2, -1, 0, 1, 2, 3, 4}
