noob plane equation question

markraz

markraz

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I'm clueless here.... What are some of the uses of a plane equation? If I had a equation such as 5x + 6y - 3z = 43 ... what is this useful for? is this used like a linear equation where you have an input and get some output?
 
markraz said:
I'm clueless here.... What are some of the uses of a plane equation? If I had a equation such as 5x + 6y - 3z = 43 ... what is this useful for? is this used like a linear equation where you have an input and get some output?
Click to expand...
Do you know the use for - equation of a line, equation of a circle, ellipse, etc.? If you do - please tell us.
 
Subhotosh Khan said:
Do you know the use for - equation of a line, equation of a circle, ellipse, etc.? If you do - please tell us.
Click to expand...

Thanks, yeah if you plugin numbers into y=mx+b you get a Y value back or you could solve for the other variables as well if you already knew Y. Or with circle equation x^2+y^2=r .....you can draw circles.

So I guess with a plane equation, if you have a point you can plug it in the equation and get something back? so (ax+by+cz = 0) is a function? what do these coefficients represent? the variables X,Y,Z would have to be 3D axis... what does the constant = 0 represent ? I think that's where I'm confused....

thanks
 
markraz said:
Thanks, yeah if you plugin numbers into y=mx+b you get a Y value back or you could solve for the other variables as well if you already knew Y. Or with circle equation x^2+y^2=r .....you can draw circles.

So I guess with a plane equation, if you have a point you can plug it in the equation and get something back? so (ax+by+cz = 0) is a function? what do these coefficients represent? the variables X,Y,Z would have to be 3D axis... what does the constant = 0 represent ? I think that's where I'm confused....

thanks
Click to expand...
The general equation of a straight line is Ax + By + C = 0 where m = slope = -A/B and b = y-intercept = -C/B. The terms in the equation of the plane are equivalent. It is also an equation of the line in 3-D (passing through the origin). This line is "normal"(perpendicular) to the plane.
 
thanks, so with a plane equation , do I need to for example...... have to plugin an x and y to solve for z? or x or z to solve for y? z and y to solve for x?
is this what a plane equation is used for?
 
markraz said:
thanks, so with a plane equation , do I need to for example...... have to plugin an x and y to solve for z? or x or z to solve for y? z and y to solve for x?
is this what a plane equation is used for?
Click to expand...
That is one of the multiple use (just like in y = mx +b, one of the uses is to calculate 'y' for a given 'x').
 
markraz said:
I'm clueless here.... What are some of the uses of a plane equation? If I had a equation such as 5x + 6y - 3z = 43 ... what is this useful for? is this used like a linear equation where you have an input and get some output?
Click to expand...
Do you know what a plane is? An equation of a line gives you a relationship between (usually) x and y. The points on the line are the set of points that have this special relationship between x and y.
A plane is similar with three variables (3-D)
 
Subhotosh Khan said:
That is one of the multiple use (just like in y = mx +b, one of the uses is to calculate 'y' for a given 'x').
Click to expand...

Thanks.. I have googled extensively for "uses for a plane equation"... "what are plane equations used for" etc....
I can't find any specfic bullet points on the various usages, it's almost as if it's so simple no one sees the need to explain it in a tutorial?? not sure

Hate to be a pain but can you guys post a few quick keywords for plane usages?? I can google the details

I appreciate your help, thank you
 
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