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**Jack A****Guest**

Hello,

After completing a page of Simultaneous Equations i am stuck with this. suddenly i have x and y's everywhere, and keep rearaging it wrong. please show me what to do. even if its just a little clue.

Solve for x and y:

4 + (4y ÷ x) = -4x^-1 and x^2 + 7xy = 19x

Thanks, J

**ryos****Member**- Registered: 2005-08-04
- Posts: 394

4 + 4y / x = 1 / -4x -> multiply by x

4x + 4y = -1/4

4y = -4x - 1/4

y = -x - 1/16

x^2 + 7xy = 19x -> divide by x

x + 7y = 19

x = 19 - 7y

I would use the substitution method to solve the system:

y = -(19 - 7y) - 1/16

y = 7y - 19 - 1/16

-6y = -305 / 16

y = 305 / 96

*Last edited by ryos (2005-10-20 12:27:12)*

El que pega primero pega dos veces.

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