A = [-10 0 -100; 2 -2 0; 0 0.1 0.2];
B = [10; 0; 0];
C = [0 0 1];
D = [0];
syms t
wn = C * expm(A * t) * B;
tn = [0:0.01:7];
plot(tn, yn), grid on;