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

Identify the converse of the following conditional: if a point is in the first quadrant, then its coordinates are positive. if the coordinates of a point are not positive, then the point is not in the first quadrant. if the coordinates of a point are positive, then the point is in the first quadrant. if a point is in the first quadrant, then its coordinates are positive. if a point is not in the first quadrant, then the coordinates of the point are not positive.

Which equation can be solved to find one of the missing side lengths in the triangle? cos(60o) = cos(60o) = cos(60o) = cos(60o) = mark this and return