Question

Given that -4 11 years ago

Answer 1

just arrange it in order like:
-4 < x < -1
2 < y < 7
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-4-2 < x-y < -1-7
or -6 < x-y < -8 which give us x-y< -8 or x-y > -6 , like
Imitate for others

Answer 2

Thanks a bunch.