[tex]1)5x(x - 3) = {5x}^{2} - 15x[/tex]
[tex]2) - 3a(4 - a) = - 12a + 3 {a}^{2} [/tex]
[tex]3)(3x - 2)2a = 6xa - 4a[/tex]
[tex]4)(6 {x}^{2} - 3x)( - 5x) = - 30 {x}^{3} + 15 {x}^{2} [/tex]
[tex]5) - 2 {y}^{3} (5 - 4y) = - 10 {y}^{3} + 8 {y}^{4} [/tex]