[tex]2(4 - 5x) - 3 = 15 \\ 8 - 10x - 3 = 15 \\ - 10x = 15 - 8 + 3 \\ - 10x = 10 \\ x = - 1[/tex]
[tex] \frac{2}{3} x - x + \frac{9}{6} = \frac{1}{2} \\ \frac{6 \times 2}{3} x - 6x + 9 = \frac{6}{2} \\ \frac{12}{3} x - 6x + 9 = 3 \\ 4x - 6x + 9 = 3 \\ - 2x = 3 - 9 \\ - 2x = - 6 \\ x = 3[/tex]
[tex] \frac{5}{6} x = 1 \frac{1}{4} \\ \frac{5}{6} x = \frac{5}{4} \\ \frac{10}{12} x = \frac{15}{12} \\ 10x = 15 \\ x = 1.5[/tex]
[tex]4 {x}^{2} -( 6 + x)(3 + 4x) = 0 \\ 4 {x}^{2} - (18 + 24x + 3x + 4 {x}^{2} ) = 0 \\ 4 {x}^{2} - 18 - 24x - 3x - 4 {x}^{2} = 0 \\ - 24x - 3x = 18 \\ - 27x = 18 \\ x = - \frac{18}{27} = - \frac{2}{3} [/tex]