Equation of Plane: Passes (5,-5,5), Perp to 3x-2z+1=0 & 4x+3y+7=0

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Homework Statement


Determine the equation of the plane that passes through (5,-5,5) and is perpendicular to the lines of intersection of the planes 3x-2z+1=0 and 4x+3y+7=0

Homework Equations



Ax+By+Cz+D=0

The Attempt at a Solution



I found the cross product of the normals of the planes given. Then used that as the direction vector of the line of intersection. Then I let z=0 and solved for x and y using the equations of the planes given in order to find a point on the line of intersection. The equation for the line of intersection is r=(-1/3,-17/9,0) + s(6,8,9).

I'm not sure what to do now. Can someone please explain?
 
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molly16 said:

Homework Statement


Determine the equation of the plane that passes through (5,-5,5) and is perpendicular to the lines of intersection of the planes 3x-2z+1=0 and 4x+3y+7=0


Homework Equations



Ax+By+Cz+D=0

The Attempt at a Solution



I found the cross product of the normals of the planes given. Then used that as the direction vector of the line of intersection. Then I let z=0 and solved for x and y using the equations of the planes given in order to find a point on the line of intersection.
Great! Now use the fact that if <A, B, C> is the normal to the plane and the plane contains the point (x_0, y_0, z_0) then the plane is given by A(x- x_0)+ B(y- y_0)+ C(z- z_0)= 0. Of course, you use (x_0, y_0, z_0)= (5, -5, 5).<br /> <br /> <blockquote data-attributes="" data-quote="" data-source="" class="bbCodeBlock bbCodeBlock--expandable bbCodeBlock--quote js-expandWatch"> <div class="bbCodeBlock-content"> <div class="bbCodeBlock-expandContent js-expandContent "> The equation for the line of intersection is r=(-1/3,-17/9,0) + s(6,8,9).<br /> <br /> I&#039;m not sure what to do now. Can someone please explain? </div> </div> </blockquote> The &quot;equation of the line of intersection&quot; is irrelevant. The point you are given is not near that line.
 
Ohhh I see! Thanks for the help!
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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