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-Consider the following system of equations:--57 - 25How many solutions does the system have?zeroonetwo

-Consider the following system of equations:--57 - 25How many solutions does the system-example-1
User Tudor Luca
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1 Answer

13 votes
13 votes

Given the system of equations:


\begin{cases}-(x^2)/(3)=-(5)/(6)+(y^2)/(3)\ldots(1) \\ 5y^2=(25)/(2)-5x^2\ldots(2)\end{cases}

We multiply by 6 the equation (1):


\begin{gathered} -(6\cdot x^2)/(3)=-(6\cdot5)/(6)+(6\cdot y^2)/(3) \\ \Rightarrow-2x^2=-5+2y^2 \\ \Rightarrow2x^2+2y^2=5\ldots(1^(\prime)) \end{gathered}

Now, we multiply by 2/5 on the equation (2):


\begin{gathered} (2)/(5)\cdot5y^2=(2)/(5)\cdot(25)/(2)-(2)/(5)\cdot5x^2 \\ \Rightarrow2y^2=5-2x^2 \\ \Rightarrow2x^2+2y^2=5\ldots(2^(\prime)) \end{gathered}

We can see that both equations (1') and (2') are equal, so we conclude that there are infinitely many solutions.

User Ben Duffin
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