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Need help with this if anyone can

Simplify a7/a4 a) 1/a3 b)-a/a2 c)a4/a3 d)a3

Which approach to the theory-and-research cycle does the following sequence reflect: (1) specific observations suggest generalizations, (2) generalizations produce a tentative theory, (3) the theory is tested through the formation of hypotheses, and (4) hypotheses may provide suggestions for additional observations?

Me complete this proof! prove that a quadrilateral is a square. me with the steps for this proof.