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F. Incorrect. You may have started by correctly multiplying all the matrix elementsby $5$: $\left[\begin{array}{cc}5& -4\\ 5& 0\end{array}\right]\left[\begin{array}{cc}5& 2\\ 5& -5\end{array}\right]=\left[\begin{array}{c}-20\\ 0\end{array}\right]\left[\begin{array}{c}10\\ -25\end{array}\right]$ . Then, you may have incorrectly added the elements in the same column: $\left[\begin{array}{cc}-20+0& 10+-25\end{array}\right]=\left[\begin{array}{cc}-20& -15\end{array}\right]$ .

G. Incorrect. You may have started by correctly multiplying all the matrix elementsby $5$: $\left[\begin{array}{cc}5\left(-4\right)& 5\left(2\right)\\ 5\left(0\right)& 5\left(-5\right)\end{array}\right]=\left[\begin{array}{cc}-20& 10\\ 0& -25\end{array}\right]$. Then, you may have incorrectly added the elements in the same row: $\left[\begin{array}{c}-20+10\\ 0+-25\end{array}\right]=\left[\begin{array}{c}-10\\ -25\end{array}\right]$.

H. Incorrect. You may have added $5$ to each of the matrix elements rather than multiplying: $5\left[\begin{array}{cc}-4& 2\\ 0& -5\end{array}\right]\to \left[\begin{array}{cc}5+\left(-4\right)& 5+2\\ 5+0& 5+\left(-5\right)\end{array}\right]=\left[\begin{array}{cc}1& 7\\ 5& 0\end{array}\right]$.

J. Correct. When multiplying a matrix by a number, distribute that number to each ofthematrix elements. Here, each element in the matrix will be multiplied by $5$: $5\left[\begin{array}{cc}-4& 2\\ 0& -5\end{array}\right]=\left[\begin{array}{cc}5\left(-4\right)& 5\left(2\right)\\ 5\left(0\right)& 5\left(-5\right)\end{array}\right]=\left[\begin{array}{cc}-20& 10\\ 0& -25\end{array}\right]$.