System of equations with 2 parameters

AI Thread Summary
The discussion revolves around solving a system of two equations involving quadratic terms. The equations are complex, and initial attempts to isolate variables lead to complicated expressions. A suggestion is made to rewrite the second equation to express x in terms of y and substitute it into the first equation. Additionally, the equations can be interpreted as circles, allowing for the identification of their centers and the slope of the line connecting them. This approach can help find the intersection points more easily, particularly by determining the slope of the common chord.
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Homework Statement


I have a system of two equations:

3*x^2 - x + 3*y^2 = 0
2*x^2 - y + 2*y^2 = 0

Homework Equations





The Attempt at a Solution


I don't know how to express one with the other.I mean I can either have x = 3*y^2 + 3*x^2 or y = y = -2*y^2 - 2*x^2 and in both cases it becomes an utter mess.What can I do?
 
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I would modify the second equation to get x^2 = ... and therefore x = ... and use this in the first equation.
 
Here's another suggestion. You can see by inspection that (0,0) is one intersection point. Since both equations represent circles, put them in standard form and locate their centers. Determine the slope ##m_1## of the line of centers. The slope of the common chord between their intersection points will be ##m_2=-\frac 1 {m_1}##. The line through the origin with that slope ##m_2## whose equation is ##y=m_2x## will pass through the other intersection point. Solve that with one of your circles. It works out pretty easily.
 
One more suggestion: can you spot a multiplier that makes the quadratic terms in one equation the same as those in the other?
 

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