[tex] - 3n \times 5m \times ( - 2) = 10 \times 3nm = 30nm[/tex]

[tex] - 7n + 8m - 13n - 3m = ( - 7 - 13)n + (8 - 3)m = - 20n + 5m[/tex]

[tex]10 - 4d - 12 + 4d = 10 - 12 = - 2[/tex]

[tex](c - 5d) - ( - d + 5c) = c - 5d + d - 5c = (1 - 5)c + (1 - 5)d = - 4c - 4d[/tex]

[tex] - 4(x - 2) + 2(6x - 1) = - 4x + 8 + 12x - 2 = 8x + 6[/tex]

[tex]5(a - 2.4) - 7( - a + 1.2) = 5a - 12 + 7a - 8.4 = 12a - 20.4[/tex]

[tex]9.6 \div (8.9 - 11.3) - ( - 4.64) \div ( - 5.8) = 9.6 \div ( - 2.4) - 0.8 = - 4 - 0.8 = - 4.8[/tex]

[tex]7x - 9x = 0.38 \\ - 2x = 0.38 \\ x = 0.38 \div ( - 2) \\ x = - 0.19[/tex]

[tex]14x - 8x = - 7.2 \\ 6x = - 7.2 \\ x = - 7.2 \div 6 \\ x = - 1.2[/tex]

[tex]1.9x - 0.2x - 2.4x = - 1.12 \\ - 0.7x = - 1.12 \\ x = - 1.12 \div ( - 0.7) \\ x = - 11.2 \div ( - 7) \\ x = 1.6[/tex]