Question

what should be subtracted from x/y to make it y/x?

Answer 1

hope it helped
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Answer 2

x/y-b=y/x

x/y-y/x=b

x^2-y^2/xy=b

now put the value of b in first eq

x/y-(x^2-y^2/xy)=y/x

x/y-x^2+y^2/xy=y/x

x^2-x^2+y^2/xy=y/x

y^2/xy=y/x

y/x=y/x