Equation for Finding Solutions of x and y

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  • Thread starter Albert1
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In summary, the author found a solution to an equation in terms of x and y. However, he made a mistake in the process. He incorrectly assumed that $x^2+y^2=x^2$. After simplifying the equation, he found that $3y=k*x$ where $k$ is an integer.
  • #1
Albert1
1,221
0
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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  • #2
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?
 
  • #3
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
 
  • #4
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:
  • #5
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 ( ) ?
 
  • #6
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
 
  • #7
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:
  • #8
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)
 
  • #9
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
 

FAQ: Equation for Finding Solutions of x and y

1. What is the process of finding solutions to an equation?

The process of finding solutions to an equation involves manipulating the equation algebraically to isolate the variable on one side and solve for its value.

2. How do I know if I have found all the solutions to an equation?

If the equation is a linear equation, you can check your solution by substituting it back into the original equation. If it satisfies the equation, then it is a valid solution. For non-linear equations, it may be necessary to use a graphing calculator or other methods to verify all possible solutions.

3. Can an equation have more than one solution?

Yes, an equation can have multiple solutions, depending on the type of equation and the number of variables involved. Some equations, like quadratic equations, can have both real and complex solutions.

4. What is the difference between real and complex solutions?

Real solutions are values that can be represented on the number line, while complex solutions involve imaginary numbers and cannot be represented on the number line. Complex solutions are often in the form of a + bi, where a and b are real numbers and i is the imaginary unit.

5. Are there any tricks or shortcuts for finding solutions to equations?

There are some common methods for solving certain types of equations, such as using the quadratic formula for quadratic equations or using the substitution method for systems of equations. However, there is no universal trick or shortcut that works for all equations. Practice and familiarity with different types of equations can make the process easier.

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