MHB Find the equation of the plane given a point and two planes

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To find the equation of a plane that passes through the point (1,3,8) and is perpendicular to the line of intersection of the planes defined by 3x−2z+1=0 and 4x+3y+7=0, the cross product of the normals of these planes is needed to determine the direction vector. The equation can be expressed in various forms, but using the point is essential for defining a unique plane. The general form of the plane's equation can be written as n1(x - 1) + n2(y - 3) + n3(z - 8) = 0, where N is the direction vector obtained from the cross product. This approach ensures the plane is correctly defined relative to the given point and the intersection of the planes.
sawdee
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I've done a question similar to this, however this one has no complete equations i can solve for.

Determine the equation of the plane that passes through (1,3,8) and is perpendicular to the line of intersection of the planes 3x−2z+1=0 and 4x+3y+7=0.

I know to take the cross product of the two normals to get my new direction vector, but I am stuck at that point. What form should this be written in and further, can I use the given point?
 
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sawdee said:
I've done a question similar to this, however this one has no complete equations i can solve for.
You're asked to find the equation of the plane with the given point

sawdee said:
Determine the equation of the plane that passes through (1,3,8) and is perpendicular to the line of intersection of the planes 3x−2z+1=0 and 4x+3y+7=0.

sawdee said:
I know to take the cross product of the two normals to get my new direction vector,
Yes, that will work.

sawdee said:
but I am stuck at that point. What form should this be written in and further, can I use the given point?
There are several different forms of the equation of a plane, so unless the grader is especially particular, it doesn't matter much what form you use.
You have to use the given point in order to get a unique plane. If N is the direction of the intersection of the given planes (and hence is normal to the plane you want), then the equation of the plane is ##n_1(x - 1) + n_2(y - 3) + n_3(z -8) = 0##, where ##\vec N = <n_1, n_2, n_3>##.
 
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