To find the value of t, we need to set X1 equal to X2:

20-20t = -5+10t

Now, let's solve for t:

20 + 5 = 10t + 20t
25 = 30t
t = 25/30
t = 5/6

Therefore, the value of t is 5/6.

To find the value of X, we can substitute the value of t back into either X1 or X2:

X1 = 20 - 20(5/6)
X1 = 20 - 100/6
X1 = 20 - 16.67
X1 ≈ 3.33

Therefore, the value of X is approximately 3.33.