Matrix Operations

A2={{-3,-3,-6},{-4,-7,8}};
B2={{2,8,7},{-5,-6,-2},{-8,4,-8},{7,4,-6}};
C2={{-2,-4},{3,-5}};
D2={{-2,-3,-1,3},{-2,-9,8,9}};
alpha2=2; beta2 =-5;
M=alpha2*A2.Transpose[B2]+beta2*Transpose[C2].D2
MatrixForm[M]
MatrixPlot[M,ColorFunction->"CandyColors"]