Can i get some help with this question please

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What is the missing reason in step 5? linear pair postulategivendefinition of complementary anglescongruent complements theorem

Determine the fraction of total interest owed. after the fourth month of a 12-month loan: the numerator is: {(n + ) + (n + ) + (n + ) + (n + )} = , and the denominator is: {(n) + (n + 1) + + (n + )} = . therefore, the fraction is numerator/denominator (to the nearest tenth) =

Which answer goes into the box? (90° clockwise rotation, 90° counter clockwise rotation, translation, or glide reflection)