Use deductive reasoning to prove that the base angles of an equilateral triangle are congruent.

Use deductive reasoning to prove that the opposite angles of a cyclic quadrilateral are supplementary.

Use deductive reasoning to prove that if two angles of a triangle are congruent, then the sides opposite those angles are also congruent. Which theorem supports this statement?

Deductively prove that the angles in a linear pair are supplementary.

Deductively prove that the diagonals of a parallelogram bisect each other.

Deductively prove that if a line is parallel to one side of a triangle and intersects the other two sides, it divides those sides proportionally. Which theorem supports this statement?

Use deductive reasoning to prove that the opposite sides of a rectangle are congruent.

Deductively prove that the opposite angles of a parallelogram are congruent. Which theorem supports this statement?

Use deductive reasoning to prove that in a right triangle, the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the legs. Which theorem supports this statement?

Use deductive reasoning to prove that in a cyclic quadrilateral, the opposite angles are supplementary. Which theorem supports this statement?