Completing the square with x and y?

grotesqueer shared this question 7 months ago
Answered

Is completing the square possible when the equation has both x and y? For example

x^2 + y^2 - 3x + y -1/4 would be (x - 3/2)^2 + (y + 1/2)^2 - 9/4, but can you do that with Geogebra?

Comments (5)

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Yup, enter

x^2 + y^2 - 3x + y -1/4 = 0

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What do you mean? Typing that alone doesn't do it. Do I need a command in front of it and if so, what command? And this is in CAS, or?

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You might need to right-click and change the display form - it will work only in GeoGebra Classic


https://www.geogebra.org/m/qchmhpab

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It is true that there is no command to transform the polygon :

P(x)= x² + y² - 3x + y - 1 / 4 = 0

into

Q(x) = (x - 3 / 2)² + (y + 1 / 2)² - 11 / 4 = 0

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You can build an user fonction (a tool) using commands :

Center(c) and radius(c) :

to display the expression you like.

(x-x(center(c))+(y-y(center(c))=radius(c)^2.

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