If α and β are the zeroes of the polynomial f(x)=x²-5x+k and α- β =-1, find the value of k

If α and β are the zeroes of the polynomial f(x)=x²-5x+k and α- β

1.	If α and β are the zeroes of the polynomial f(x)=x²-5x+k and α- β =-1, find the value of k
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