MHB How to find the intersection point between two lines

AI Thread Summary
To find the intersection point between two lines defined by their parametric equations, different parameters must be used for each line. The equations provided are line 1: r = (3,1,-1) + s(1,2,3) and line 2: r = (2,5,0) + t(1,-1,1). The goal is to find values for s and t such that the resulting position vectors are equal. It is clarified that the parameters cannot be the same for both lines, as they represent distinct lines. Understanding this distinction is crucial for solving the intersection problem correctly.
Raerin
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How to find the intersection point between two lines?

line 1: r = (3,1,-1) + s(1,2,3)
line 2: r = (2,5,0) + s(1,-1,1)
 
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Raerin said:
line 1: r = (3,1,-1) + s(1,2,3)
line 2: r = (2,5,0) + s(1,-1,1)

Hey Raerin! ;)

Let's use a different parameter in both of those line equations.

line 1: r = (3,1,-1) + s(1,2,3)
line 2: r = (2,5,0) + t(1,-1,1)

We're looking for an $s$ and a $t$, such that the resulting r is the same...Btw, perhaps you could also put your question inside your post instead of only as the title of the thread.
Your post looks a bit out of context now. :o
 
I like Serena said:
Hey Raerin! ;)

Let's use a different parameter in both of those line equations.

line 1: r = (3,1,-1) + s(1,2,3)
line 2: r = (2,5,0) + t(1,-1,1)

We're looking for an $s$ and a $t$, such that the resulting r is the same...Btw, perhaps you could also put your question inside your post instead of only as the title of the thread.
Your post looks a bit out of context now. :o
Haha! It Was a typo I see! I Was trying and trying, i Was like how can $$3+s= 2+s$$

Regards,
$$|\pi\rangle$$
 
I like Serena said:
Hey Raerin! ;)

Let's use a different parameter in both of those line equations.

line 1: r = (3,1,-1) + s(1,2,3)
line 2: r = (2,5,0) + t(1,-1,1)

We're looking for an $s$ and a $t$, such that the resulting r is the same...Btw, perhaps you could also put your question inside your post instead of only as the title of the thread.
Your post looks a bit out of context now. :o

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So it's not possible for both parameters to be s? Then there's a mistake in the question. I guess I don't need help anymore. Thanks!
 
Raerin said:
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So it's not possible for both parameters to be s? Then there's a mistake in the question. I guess I don't need help anymore. Thanks!

It's not really a mistake in the question.
The general form of a line equation is $\vec r = \vec a + s \vec d$.
However, when you intersect 2 different lines with such an equation, you have to realize that the parameters $s$ in those 2 line equations are distinct.
 
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