I have an idea that in order to get the equation given only the lines, it requires to do cross product and solving for the coordinates that satisfies the given two lines.

The problem is that only intersecting lines of planes are given. I have no problem for the cross product but I am confused for finding the coordinates since the answer would be infinite solution. What could be another way to find the points?

The original problem goes this way.

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> Determine an equation for each of the lines described below.
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> > line of intersection of the planes 2x - y + z = -1 and x + 4y - z = 2.
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