[tex]1)y \div 6 + 3.8 = 4.7 \\ y \div 6 = 4.7 - 3.8 \\ y \div 6 = 0.9 \\ y = 0.9 \times 6 \\ y = 5.4[/tex]

[tex]0.4(a - 3) = 0.7(6a - 5) + 1.16 \\ 0.4a - 1.2 = 4.2a - 3.5 + 1.16 \\ 0.4a - 4.2a = 1.2 - 3.5 + 1.16 \\ 3.8a = - 1.14 \\ a = - 0.3[/tex]

[tex]2(x + 4) + 3(7 + x) = 59 \\ 2x + 8 + 21 + 3x = 59 \\ 5x = 59 - 8 - 21 \\ 5x = 30 \\ x = 6[/tex]

[tex] \frac{7}{2} b - 1.2b + 0.2b = 9 \\ 3.5b - 1.2b + 0.2b = 9 \\ 2.5b = 9 \\ b = 3.6[/tex]