Q .44.

Question

determine whether the given pairs of lines are parallel, identical, intersecting, or skew. If the lines are parallel, compute the distance between them. If the lines intersect, find the point of intersection and the angle at which the lines intersect. 

r1(t)=4+5t,6,7-2t

r2(t)=6-4t,-3+3t,-1+4t

Step-by-Step Solution

Verified
Answer

The lines are not parallel andthe intersecting point of the lines is(-6,6,11) 

1Step 1:Given information

The given pairs of lines are 

r1(t)=4+5t,6,7-2t

r2(t)=6-4t,-3+3t,-1+4t

2Step 2:Calculation

Consider the two lines,

r1(t)=(4+5t,6,7-2t)....eq(1)

r2(t)=(6-4t,-3+3t,-1+4t) ....eq(2)

For the line equation

(1) that is for r1(t)=(4+5t,6,7-2t) the direction vector is,

d1=(5,0,-2) where d1 is the direction vector 

For the line equation

(2) that is for r2(t)=(6-4t,-3+3t,-1+4t) the direction vector is

d2=(-4,3,4). where d2 is the direction vector 

Here the direction vectors d1,d2 are not scalar multiples of each other.

Thus, the lines are not parallel.


Thus, the lines r1(t)=(4+5t,6,7-2t)and r2(t)=(6-4t,-3+3t,-1+4t) are not parallel lines.

Now calculate the point of intersection of two lines.

To calculate the intersection point of two equations, replace the parameter t by u in the equation(2) that is r2(t)=(6-4t,-3+3t,-1+4t).

Then,

r2(u)=(6-4u,-3+3u,-1+4u)

Equate the values of equations,

r1(t)=(4+5t,6,7-2t) and r2(u)=(6-4u,-3+3u,-1+4u)

4+5 t=6-4 u ...eq(3)

6=-3+3 u ...eq(4)

7-2 t=-1+4 u ...eq(5)

Take the equation (4) that is 6=-3+3 u.

6+3=3 u

u=3

Substitute u=3 in the equation

(3) that is4+5 t=6-4 u.

 4+5t=6-4·3

4+5 t=-6

t=-2

 Substitute t=-2 in r1(t)=(4+5t,6,7-2t)

r1(-2)=(4+5·-2,6,7-2·-2)

r1(-2)=(-6,6,11)

 Now substitute u=3 in the equation r2(u)=(6-4u,-3+3u,-1+4u)

r2(3)=(6-4·3,-3+3·3,-1+4·3)

r2(3)=(-6,6,11)

 The intersecting point of the lines is (-6,6,11)