Continuous-Time System:
a1 = 8, a0 = 18, b1 = 8, b0 = -4, 

Your excitation signal x(t) consists of straight lines connecting these points.
It has been zero up until the first time and is zero after the last time.

t = 1.93985, x(t) = 0
t = 1.93985, x(t) = -23
t = 2.56004, x(t) = -23
t = 2.56004, x(t) = 18
t = 7.53221, x(t) = 18
t = 7.53221, x(t) = -8
t = 8.43413, x(t) = -8
t = 8.43413, x(t) = 4
t = 9.23172, x(t) = 4
t = 9.23172, x(t) = 0
t = 16.197, x(t) = 0

Discrete-Time System:
a0 = 15, a1 = 12, b0 = -4, b1 = 5, 
0 <= n < 4,  x[n] = 0
4 <= n < 7,  x[n] = 11
7 <= n < 11,  x[n] = 6
11 <= n < 12,  x[n] = 10
12 <= n < 16,  x[n] = -9
16 <= n < 27,  x[n] = 0

x[n] has been zero up until the first time and is zero after the last time.