Question 9390
Solve for y:
x+y=4
y=4-x

Substitute into the second equation:
x-y=5
x-(4-x) = 5
x-4 +x = 5
2x - 4 = 5
2x = 9
x=9/2 or 4.5


y = 4-x
y = 4 - 4.5
y = -.5 or -1/2


Independent, since there is a unique solution.


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