Questions tagged [analytic-geometry]

Questions on the use of algebraic techniques for proving geometric facts. Analytic Geometry is a branch of algebra that is used to model geometric objects - points, (straight) lines, and circles being the most basic of these. It is concerned with defining and representing geometrical shapes in a numerical way.

Analytic geometry, also called coordinate geometry, mathematical subject in which algebraic symbolism and methods are used to represent and solve problems in geometry.

The importance of analytic geometry is that it establishes a correspondence between geometric curves and algebraic equations. This correspondence makes it possible to reformulate problems in geometry as equivalent problems in algebra, and vice versa; the methods of either subject can then be used to solve problems in the other.

Analytic geometry was introduced by René Descartes in $1637$ and was of fundamental importance in the development of the calculus by Sir Isaac Newton and G. W. Leibniz in the late $17^{th}$ cent. More recently it has served as the basis for the modern development and exploitation of algebraic geometry.

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Locus of a point that satisfy a condition on the square of distances to two lines and their intersection

Find the locus of a point such that the square of its distance to the point of intersection of two perpendicular lines is equal to the sum of its distances to those lines. Assume $P(x,y)$ is any point of the locus,…
mobzopi
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Mirorring a set of Points

Let's say I have a cloud of points, and I know the equation of the symmetry plane. I'd like to mirror every single point with respect to this plane. It might be much simpler than I think, but I have some difficulties on finding a way to do that in…
G4bri3l
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How to see a plane is tangent to a sphere from their equations

Say you have two equations with three variables, the first is the equation of the surface of a sphere and the second of a plane. In this case they intersect in a point $(1,0,0)$. The only way I know to find this point is to rewrite the equation of…
Jus
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finding a point of intersection

I need to find a point on the $y-axis$ so the tangents from that point to circles: $(x-6)^2+(y-3)^2=16$, $(x-4)^2+(y-6)^2=5$ are equal in length. I tried to use $(x-a)(x_1-a)+(y-b)(y_1-b)$ but it was quite messy. i also tried to use…
debii
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Find an unknown coefficient in a line equation...

So, I have to find the unknown coefficient in this line: $$x+y+C=0$$ so that it is a tangent to this circle: $$x^2+y^2-5x-7y+6=0$$ I've transformed the circle equation to this form: $$(x-\frac{5}{2})^2+(y-\frac{7}{2})^2=\frac{25}{2}$$ But I can't…
A6SE
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Finding the equations of the lines and tangent to the circle

Find the equations of the lines through $(2,0)$ and tangent to the circle $x^2+y^2=1$. I tried to solve this and I know the right answer but I just can't solve this. The right answer: $\sqrt{3}y=x-2$ or $\sqrt{3}y=2-x$.
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Analytic Geometry

How does one solve: Find the equation of the circle which has it's center on the line $y= 3-x$ , and which has as tangents the lines $ 2y-x = 22, $ $ 2x+y=11 $ ?
Bak1139
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Circle Tangent question

I would like to ask for assiatance on the following: Find the eqation of a circle, with a radius of$\sqrt 2$ , which also has as tangetns the lines: $ y=x+2 $ , $ y=-7x $. It is known that the circle is in the first quadrant. A possible solution…
Bak1139
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Curve equation - help in understanding

OK, I wasn't on a class regarding this type of excercises. I got the notes from the lesson but have no idea how is it working. I hope you'll be able to clarify: Determine the equation of the curve being a set of the middles of all the chords of…
Bringiton
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Perpendicular form of the straight line equation.

There are $5$ to $6$ standard forms of the straight line equation. for example slope intercept form, two intercept form, point slope form and perpendicular form. I have clear visualization of all forms except the perpendicular form. Can any one…
zonnie
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exercise with lines algebra

This is an exercise I really can't solve by myself. 1) Let A(1,-1,0) a point on a line (e) line 2) Let (d) be a line perdicular to (e), given by a parametric equation. How I can find the equation of (e)?
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points of intersection of two circles drawn on a sphere

How does one write and thereafter solve the equations to find the points of intersection of two overlapping circles drawn on the surface of a sphere? I am looking for a simple understandable solution that one could enter into a calculator to solve…
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Find Points in The Cube

In the cube $ABCDA'B'C'D'$, we have $3\overrightarrow{AM}=\overrightarrow{MD}$ and $2\overrightarrow{D'N}=\overrightarrow{NB'}$. Find the points $M$ and $N$ in the cube; So, i can't find a way to discover these points. Every method I've tried ended…
Student
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Analytic Geometry question, planes and lines

Let there be a plane going through three points $(0,2,-9), (0,-1,0), (-\frac{3}{m},1,-3)$. For which value of $m$ is the line $l: (3,0,-9)+t(2m,-5,7)$ onto (or 'inside') the plane? Not sure how to do this. Thanks in advance!
Jim
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shortest distance between two cones in 3-dim space

How can I find the shortest distance between two cones in 3-dim space? cone 1: apex - $(x_{0}, y_{0}, z_{0})$ angle - $\alpha_{0}$ base circle - $(cx_{0}, cy_{0}, cz_{0}, r_{0})$ cone 2: apex - $(x_{1}, y_{1}, z_{1})$ angle - $\alpha_{1}$ base…
Bo Xiao
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