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# Can someone help me to solve this two variable quadratic? watch

I have tried to factorise it but I can only group it to this:

This is close but I cannot seem to finish it off.

2. (Original post by milan_tom)
-xy + 2x + 2y + 4 = 0

I have tried to factorise it but I can only group it to this:
-x (y - 2) + 2 (y + 2) = 0
This is close but I cannot seem to finish it off.

Get all the terms in y over to one side of the equation:

Can you take it from there?
3. (Original post by Gregorius)
Get all the terms in y over to one side of the equation:

Can you take it from there?
Let me try:

How can I simplify it from here?
4. (Original post by milan_tom)
Let me try:
xy - 2y = 2x 4
y(x-2) = 2x 4
y = (2x+4)/x-2
y = (2(x+4))/x-2

How can I simplify it from here?
Your final line should be y=(2(x+2))/x-2, you didn’t factor out the 4.
5. (Original post by milan_tom)
Let me try:
xy - 2y = 2x + 4
y(x-2) = 2x+4
y = (2x+4)/x-2
y = (2(x+4))/x-2

How can I simplify it from here?
That's as far as you need to take it (modulo correcting the factoring out pointed out by @Y11_Maths) So a final answer of

should do nicely.
6. (Original post by Gregorius)
That's as far as you need to take it (modulo correcting the factoring out pointed out by @Y11_Maths) So a final answer of

should do nicely.
I need to solve for x and y.
7. (Original post by Y11_Maths)
Your final line should be y=(2(x+2))/x-2, you didn’t factor out the 4.
Yes, sorry, that was a typo.
8. (Original post by milan_tom)
I need to solve for x and y.
You have! Equations like this will not have simple x = a y = b type solutions. To see this, this of the analogous, but simpler, equation xy = 1. The solution to it is y = 1/x (clearly!)
9. (Original post by Gregorius)
You have! Equations like this will not have simple x = a y = b type solutions. To see this, this of the analogous, but simpler, equation xy = 1. The solution to it is y = 1/x (clearly!)
Thanks!
10. (Original post by milan_tom)
I need to solve for x and y.
To get numerical values for x and y you need another equation.

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