Lines and Planes: How Do They Intersect?

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The discussion focuses on finding the intersection of two lines, L_1 and L_2, with a plane P. For Part A, the user attempts to solve for the parameter t to find the intersection point of L_1 with the plane, suggesting t=2 but is uncertain about verifying if this point lies within the plane. The user acknowledges the parametric nature of the line equations and the implicit nature of the plane equation, indicating a method to generate points on the lines and check their validity against the plane. Part B, concerning the shortest distance between L_1 and L_2, has not yet been attempted. The conversation emphasizes understanding the relationship between parametric lines and implicit planes for solving intersection problems.
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Homework Statement



The Question Says:

Given tow lines and a plane:

The First Line is:L_1:(x y z):= (-4 3 4)*t +(7 2 -1)

The Second Line:L_2:(x y z):=( -3 5 5)*s +(-1 62 -11)

The Plane is :P:(x y z)dotted with(9 -2 3)=-4

(A)At which point do L_1 and P intersect? Check if this point lies in the plane P

(B) What is the shortest distance between L_1 and L_2?
The attempt at a solution:

For Part A

I have tried to do the following:

(-4*t+7)*(9)
(3*t+2)*(-2)
(4*t-1)*(3)
all equal to =-4

then solve for t
t=2

I am not sure if this is correct, for the next part "Check if this point lies in the plane P" I am not sure how to do so

for Part B I didn't try it yet , but I will do after a bit.
 
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These line equations are parametric, so they say that if you choose any t (or s in L_2), you'll get a point on the line. The plane equations are implicit, so they say that for any point, if the equation is correct for it, that point is on the plane.
Now you have a method to generate a point on the line and a method to check if a point is on a plane. If you combine the two, you get an equation with a single unknown t. Since you're asked for a point, don't forget to generate it with the line function.
 
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