Can anyone help me solve this equation system ?

In summary, the conversation discusses two methods for solving the equations x³+y³=1 and x²y+2xy²+y³=2. The first method involves solving for y in the first equation and substituting it into the second equation, resulting in an equation in terms of x only. The second method involves solving for x in the second equation using the quadratic formula. The conversation also suggests a third method where both equations are divided by y³ and then substituted with a variable r=x/y, resulting in a cubic equation in r. This can be solved by guessing a root or graphing to find a root, which can then be reduced to a quadratic to find the other two solutions.
  • #1
Dorotea
1
0
x³+y³=1
x²y+2xy²+y³=2
 
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  • #2
You could try solving the first equation for y and substituting it int the second...that will give you an equation in terms of x only.
 
  • #3
Or you could solve for x in the 2nd equation, which is quadratic in x, by using the quadratic formula.
[tex]yx^2 + 2y^2 x + y^3 -2 = 0[/tex]
You will of course get two equations for x.
 
  • #4
You could expand (x+y)3 and then substitute the values for the two expressions that you have. That would be a lot simpler.
 
  • #5
Notice that both equations only have terms of degree 3 in both variables. So one thing you could do is let r=x/y, and divide both equations by y^3. Each left-hand side will then depend only on r, and each right-hand side only on y^3. Eliminating y^3 will give you a cubic equation in r. Solve this by guessing a root, or by graphing to get a root. Once you know one root you can reduce it to a quadratic to get the other two.
 

1. How do I know if an equation system is solvable?

An equation system is solvable if it has a unique solution or if it has infinitely many solutions. You can determine this by simplifying the equations and checking if they are equivalent or if they lead to a contradiction.

2. What is the first step in solving an equation system?

The first step is to simplify the equations by combining like terms and eliminating any unnecessary variables. This will make it easier to see the relationships between the equations.

3. Can I use any method to solve an equation system?

No, the method you use will depend on the type of equation system. For example, a system of linear equations can be solved using substitution, elimination, or graphing methods, while a system of nonlinear equations may require more advanced techniques.

4. What should I do if I get stuck while solving an equation system?

If you get stuck, try going back to the beginning and checking your work. Look for any mistakes or inconsistencies, and try a different method if necessary. You can also seek help from a tutor or colleague.

5. Can technology be used to solve an equation system?

Yes, there are many online tools and software programs that can solve equation systems for you. However, it's important to understand the steps and methods involved so that you can check the accuracy of the solution.

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