SOLUTION: (k-1)x-y=5,(k+1)x+(1-k)y=(3x+1)

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Question 971836: (k-1)x-y=5,(k+1)x+(1-k)y=(3x+1)
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Substitution Method should be easiest to use.
Put both into standard form or whichever choice of forms for each you want, first.

1
kx-x-y=5
or
-y=5-%28k-1%29x
highlight_green%28y=-5%2B%28k-1%29x%29

2
%28k%2B1%29x%2B%281-k%29y=3x%2B1
%28k%2B1%29x%2B%28y-ky%29=3x%2B1
%28k%2B1%29x-3x%2By-ky=1
SUBSTITUTE,
%28k%2B1%29x-3x%2B%28%28k-1%29x-5%29-k%28%28k-1%29x-5%29=1
%28k%2B1%29x-3x%2Bkx-x-5-%28k%5E2%2Ax-kx-5k%29=1
%28k%2B1%29x-3x%2Bkx-x-5-k%5E2%2Ax%2Bkx%2B5k=1
%28k%2B1%29x-3x%2Bkx-x-k%5E2%2Ax%2Bkx=1-5k%2B5
x%28k%2B1-3%2Bk-1-k%5E2%2Bk%29=6-5k
x%28-k%5E2%2B3k-3%29=6-5k
x%28k%5E2-3k%2B3%29=5k-6, which was result of multiplication of negative 1 to both sides
highlight%28x=%285k-6%29%2F%28k%5E2-3k%2B3%29%29---------For ONE OF the variables.

Go back to y in terms of x and k, and substitute the formula for x, and simplify for the formula for y.