How Do I Solve for x and y Using Simultaneous Equations?

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To solve the simultaneous equations 2x - 3y = 1 and x² - 2xy - 3y² = -3, the user substituted the linear equation into the quadratic, resulting in a quadratic equation in y: 15y² - 2y = 13. They also derived a quadratic in x: 5x² - 6x = 9. The discussion emphasizes the importance of solving the quadratic equations for y and x using standard techniques, such as factorization. The user expressed concern about the time taken for the problem, indicating it was a practice question. Ultimately, the focus is on efficiently solving the derived quadratics to find the values of x and y.
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Crazy Simultaneous Equation ?!?

Homework Statement



Solve for x and y
1)2x - 3y = 1
2)x2 - 2xy - 3y2 = -3

Homework Equations


The Attempt at a Solution


I substituted the linear equation into the quadratic and got a quadratic with only y in it:
3.) 15y2 - 2y = 13

I then substituted the linear into eq3 and got a quadratic with only x in it:
4.) 5x2 - 6x = 9

Do I need substitute that linear into these quadratics twice more so I get 2 simultaneous quadratics with only x in them and 2 quadratics with only y in them?

I've been on this question for about half an hour now but this is a sample question from a test so there's no way I could spend that long on a single question on a test. I must be doing it wrong.
 
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where is eqn 3?
You say it has only y in it why aren't you solving it then?
 


Its a quadratic if has y^2 and y. I'll edit the post and put in all the equations I got
 


3.) 15y2 - 2y = 13
Looks good! The rest is easy - just use one of your techniques for solving a quadratic equation to find the number(s) for y.
 


Ah yea I didn't even think of factorizing or anything like that. Thanks.
 
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