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#1 2005-10-21 09:49:20
- Jack A
- Guest
Help with Evil Simultaneous Equation
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
#2 2005-10-21 10:26:12
- ryos
- Power Member
Offline
Re: Help with Evil Simultaneous Equation
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 (2005-10-21 10:27:12)
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