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Find the line through (3, 1, −2) that intersects and is perpendicular to the line x = −1 + t, y = −2 + t, z = −1 + t. (HINT: If (x0, y0, z0) is the point of intersection, find its coordinates. Enter your answers as a comma-separated list of equations.)

User Bogdacutu
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1 Answer

1 vote

Answer:

( xo , yo , zo ) = ( 1 , 0 , 1 )

Explanation:

Given:-

- A line passing through point (3, 1, −2) intersects and is perpendicular to line with coordinates:

x = −1 + t, y = −2 + t, z = −1 + t .... t = arbitrary parameter.

Find:-

The coordinates for point of intersection.

Solution:-

- The line that passes through point (3, 1, −2) = ( a, b , c ) and an a arbitrary point on the given line have the following direction vector d2 :

d2 = ( x2 , y2 , z2 )

x2 = a - ( x ) = 3 - ( -1 + t ) = 4 - t

y2 = b - ( y ) = 1 - ( -2 + t ) = 3 - t

z2 = c - ( z ) = -2 - ( -1 + t ) = -1 - t

d2 = ( 4 - t , 3 - t , -1 - t )

- The direction vector d1 of the given line is:

d1 = ( x1 , y1 , z1 )

x1 = 1

y1 = 1

z1 = 1

d1 = ( 1 , 1 , 1 )

- The dot product of two orthogonal vectors is always equal to zero:

d1.d2 = 0

( 4 - t , 3 - t , -1 - t ) . ( 1 , 1 , 1 ) = 0

- Solve for parameter (t):

(4 - t) + (3 - t) + (-1 - t) = 0

6 -3t = 0

t = 2

- The coordinates of the point of intersections can be evaluated by substituting the value of "t" into the given equation of line:

xo ( t = 2) = - 1 + 2 = 1

yo ( t = 2) = - 2 + 2 = 0

zo ( t = 2) = - 1 + 2 = 1

- The coordinates are:

( xo , yo , zo ) = ( 1 , 0 , 1 )

User KWilson
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