The given expression is
[tex](-5a+2a^2\text{ - 2)(2a - 4)}[/tex]To distribute, we would multiply the terms in each bracket individually and add or subtract where necessary. It becomes
[tex]\begin{gathered} -\text{ 5a}\times2a\text{ + (-5a}\times-4)+(2a^2\times2a)+(2a^2\times-4)+(-2\times2a)+(-2\times-4) \\ -10a^2+20a+4a^3-8a^2-4a+8 \\ 4a^3-10a^2-8a^2+20a-4a+8 \\ 4a^3-18a^2+16a\text{ + 8} \end{gathered}[/tex]