Continuous-Time System:
a1 = 12, a0 = 14, b1 = -4, b0 = -6, 

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 = 1.15898, x(t) = 0
t = 1.15898, x(t) = 3
t = 2.42633, x(t) = 3
t = 2.42633, x(t) = 4
t = 4.11394, x(t) = 4
t = 4.11394, x(t) = -18
t = 4.20411, x(t) = -18
t = 4.20411, x(t) = -12
t = 7.14156, x(t) = -12
t = 7.14156, x(t) = 0
t = 15.0713, x(t) = 0

Discrete-Time System:
a0 = -11, a1 = -9, b0 = -27, b1 = -39, 
0 <= n < 7,  x[n] = 0
7 <= n < 9,  x[n] = -20
9 <= n < 11,  x[n] = -23
11 <= n < 20,  x[n] = 0

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