How can I tell if this parametric equation intersects?

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How can I tell if this parametric equation intersects?

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Each of them $(X_1=X_2, Y_1=Y_2, Z_1=Z_2)$ are equal to $0$. Does this mean they do not intersect? Are they parallel?

I am willing to clear things up need it be, of if there's any information currently missing that you'd like to know. Thanks in advance.

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The answer is yes, they will intersect. Actually, your starting point is correct, but you need to define your problem in a mathematical way.

In brief, if there exists a pair $(t,u)$ that makes $x(t)=x(u)$ and the same for $y,z$, then you can claim they intersect. Otherwise, they don't. To be more specific, if there is a solution for
\begin{align} t+5&=4u+11\\ 2t-6&=-2u-4\\ 3t-1&=6u+11, \end{align} then these two lines intersect. The solution can be easily obtained as $(t,u)=(2,-1)$. So there is an intersection.

To check if two lines are parallel, you can wrap it up as another math problem that if $\frac{d}{dt}x(t)=|\frac{d}{du}x(u)|$ and the same for $y,z$. If the answer is yes, then these two lines are parallel.