Equation for Finding Solutions of x and y

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Discussion Overview

The discussion revolves around finding solutions for the variables $x$ and $y$ in the equation $4x+3y-2x\begin{bmatrix}\dfrac{x^2+y^2}{x^2}\end{bmatrix}=0$. Participants explore different interpretations and methods for expressing $y$ in terms of $x$, as well as clarifying the notation used in the equation.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants inquire whether the goal is to express $y$ in terms of $x$.
  • There is a question regarding the notation used, specifically whether the brackets denote the greatest integer function or simply serve as a replacement for parentheses.
  • One participant suggests that the equation can be simplified by dividing both sides by $x^2$, under the condition that $x \ne 0$.
  • A later reply clarifies that the expression simplifies to $3y = kx$, where $k$ is an integer, correcting an earlier statement about the relationship between $y$ and $x$.
  • Participants express uncertainty about the clarity of previous claims and the correctness of methods proposed.

Areas of Agreement / Disagreement

Participants generally agree on the need to express $y$ in terms of $x$, but there are multiple interpretations regarding the notation and the correctness of the proposed methods. The discussion remains unresolved regarding the best approach to finding solutions.

Contextual Notes

There are limitations regarding the assumptions made about the variables, particularly the condition $x \ne 0$, and the interpretation of the notation used in the equation.

Albert1
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find solutions of $x$ and $y$

$4x+3y-2x\begin{bmatrix}
\dfrac{x^2+y^2}{x^2}
\end{bmatrix}=0
$
 
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Re: find solutions of equation

Albert said:
find solutions of $x$ and $y$

$4x+3y-2x\begin{bmatrix}
\dfrac{x^2+y^2}{x^2}
\end{bmatrix}=0
$

Do you mean to find y in terms of x?
 
Re: find solutions of equation

Prove It said:
Do you mean to find y in terms of x?
if x,y not specialized value , then express y in terms of x
 
Re: find solutions of equation

Expand, move everything with a y to one side, and then complete the square to solve for y.
 
Last edited by a moderator:
Re: find solutions of equation

Albert said:
find solutions of $x$ and $y$

$4x+3y-2x\begin{bmatrix}
\dfrac{x^2+y^2}{x^2}
\end{bmatrix}=0
$

Is [ ] denoting the greatest integer function or is it just a bracket replacement of ( ) ?
 
Re: find solutions of equation

Evobeus said:
Is [ ] denoting the greatest integer function or is it just a bracket replacement of ( ) ?

[ ] denotes the greatest integer function
 
Albert said:
find solutions of $x$ and $y$

$4x+3y-2x\begin{bmatrix}
\dfrac{x^2+y^2}{x^2}
\end{bmatrix}=0
$

First we easily see that $x \ne 0$
So, now divide both sides of the given equation by $x$
We get,
$4+3 \frac{y}{x} -2\begin{bmatrix}
\dfrac{x^2+y^2}{x^2}
\end{bmatrix} =0$
From there we see that $\frac{y}{x}$ must be an integer.
Thus,
$y=k*x$ where $k$ is an integer.
Now replace $y$ with $k*x$ in the given equation and divide it by $x$.
This gives us
$2k^2-3k-2=0$
Solving for $k$ gives us $k=2$ or $k=-\frac{1}{2}$
Therefore,
$x$ is any non zero real number and $y=k*x$ where $k=2$ or $k=-\frac{1}{2}$
 
Last edited by a moderator:
Evobeus said:
First we easily see that $x \ne 0$
So, now divide both sides of the given equation by $x$
We get,
$4+3 \frac{y}{x} -2\begin{bmatrix}
\dfrac{x^2+y^2}{x^2}
\end{bmatrix} =0$
From there we see that $\frac{y}{x}$ must be an integer.
Thus,
$y=k*x$ where $k$ is an integer.
Now replace $y$ with $k*x$ in the given equation and divide it by $x$.
This gives us
$2k^2-3k-2=0$
Solving for $k$ gives us $k=2$ or $k=-\frac{1}{2}$
Therefore,
$x$ is any non zero real number and $y=k*x$ where $k=2$ or $k=-\frac{1}{2}$
$y=2x , \,\,\,\,\,\,\,\,\,\,\,\bigcirc \\
y=-\dfrac{x}{2}, \,\,\,\,\,\,\,\,\times$
$y=kx $
(where $k$ may or may not be an integer)
 
Evobeus said:
First we easily see that $x \ne 0$
So, now divide both sides of the given equation by $x$
We get,
$4+3 \frac{y}{x} -2\begin{bmatrix}
\dfrac{x^2+y^2}{x^2}
\end{bmatrix} =0$
From there we see that $\frac{y}{x}$ must be an integer.
Thus,
$y=k*x$ where $k$ is an integer.
Now replace $y$ with $k*x$ in the given equation and divide it by $x$.
This gives us
$2k^2-3k-2=0$
Solving for $k$ gives us $k=2$ or $k=-\frac{1}{2}$
Therefore,
$x$ is any non zero real number and $y=k*x$ where $k=2$ or $k=-\frac{1}{2}$

My solution (the one quoted above {^^} [ in this post ] ) is correct in terms of the idea or methodical procedure or algorithm (algorithm is a good word) but is wrong in terms of the answer

Although Albert's post very effectively helped me (and I am sure many who read my solution), but I cannot understand Albert's claim clearly (sorry for that --it is my fault )

Albert said:
$y=2x , \,\,\,\,\,\,\,\,\,\,\,\bigcirc \\
y=-\dfrac{x}{2}, \,\,\,\,\,\,\,\,\times$
$y=kx $
(where $k$ may or may not be an integer)
So, after spending so many words on something that could be described in a single line I describe the error and the solution again :
First : See that $x \ne 0$ [why ? ] [Reason : $x^2$ is in the denomianator ]
Second : Divide both sides of the given equation by $x^2$ [It is possible because $x \ne 0$ and $x,y \in \mathbb{R}$ ]
Third: we get an expression
$4+3*\frac{y}{x} - 2 ( \lfloor \frac{x^2+y^2}{x^2} \rfloor ) = 0$
Fourth:We get an expression
$3* \frac{y}{x}$ = integer
So ,
$3y=k*x$ where $k$ is integer.
earlier I wrote :
$y=k*x$ where $k$ is an integer but actually $\boxed{3}y=k*x$ where $k$ is an integer.

Now proceed as done in the solution and get the solution.
 
Last edited by a moderator:
  • #10
Evobeus said:
My solution (the one quoted above {^^} [ in this post ] ) is correct in terms of the idea or methodical procedure or algorithm (algorithm is a good word) but is wrong in terms of the answer

Although Albert's post very effectively helped me (and I am sure many who read my solution), but I cannot understand Albert's claim clearly (sorry for that --it is my fault )

So, after spending so many words on something that could be described in a single line I describe the error and the solution again :
First : See that $x \ne 0$ [why ? ] [Reason : $x^2$ is in the denomianator ]
Second : Divide both sides of the given equation by $x^2$ [It is possible because $x \ne 0$ and $x,y \in \mathbb{R}$ ]
Third: we get an expression
$4+3*\frac{y}{x} - 2 ( \lfloor \frac{x^2+y^2}{x^2} \rfloor ) = 0$
Fourth:We get an expression
$3* \frac{y}{x}$ = integer
So ,
$3y=k*x$ where $k$ is integer.
earlier I wrote :
$y=k*x$ where $k$ is an integer but actually $\boxed{3}y=k*x$ where $k$ is an integer.

Now proceed as done in the solution and get the solution.
so the solutions
(1)y=2x correct
(2)y=-0.5x wrong
check it again
 

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