Finding the equation of a surface?

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To find the equation of the surface where the distance from point P to the x-axis is five times the distance to the yz-plane, one must derive the relationship using the distance formula, leading to the equation 25y^2 + z^2 = x^2. For the second question, the surface equidistant from the point (-3, 0, 0) and the plane x = 3 can be established by setting the distance from a point (x, y, z) to both the point and the plane equal, resulting in the equation (x + 3)^2 + y^2 + z^2 = (x - 3)^2. Both problems require careful manipulation of distance formulas and squaring terms for simplification. The discussions highlight the importance of understanding geometric relationships in three-dimensional space to derive surface equations. Ultimately, solving these equations involves applying fundamental principles of geometry and algebra.
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Homework Statement



2 Questions.

1)Find an equation for the surface consisting of all points P for which the distance from P to the x-axis is 5 times the distance from P to the yz-plane.

2)Find an equation for the surface consisting of all points that are equidistant from the point (−3, 0, 0) and the plane x = 3.

Homework Equations





The Attempt at a Solution



1)The only thing I can think of is an ellipsoid with an equation similar to 5x^2+y^2+z^2=1

Is that correct? Or am I totally off?

2) I feel a parabolic cylinder would work here (opening facing toward point) but not sure how to find the equation.
 
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Kalookakoo said:

Homework Statement



2 Questions.

1)Find an equation for the surface consisting of all points P for which the distance from P to the x-axis is 5 times the distance from P to the yz-plane.

2)Find an equation for the surface consisting of all points that are equidistant from the point (−3, 0, 0) and the plane x = 3.

Homework Equations




The Attempt at a Solution



1)The only thing I can think of is an ellipsoid with an equation similar to 5x^2+y^2+z^2=1

Is that correct? Or am I totally off?

2) I feel a parabolic cylinder would work here (opening facing toward point) but not sure how to find the equation.

In both cases take a variable point ##(x,y,z)##, calculate the various distances, and use the given relations. You will undoubtedly have to square things to simplify the equations.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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