It is known that the solutions of binary linear equations x + 2Y = K + 21 2x + y = 1 are opposite to each other, then the reciprocal of K is K

2x+y=1
y=1-2x
∵ X and y are opposite to each other
∴y=-x
-x=1-2x
x=1
y=-1
x+2y=k+21
1+2(-1)=k+21
k=-22
1/k=-1/22

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