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More Lessons for High School Regents Exam

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High School Math based on the topics required for the Regents Exam conducted by NYSED. Theorems about Parallelograms: Opposite sides are congruent, Opposite angles are congruent, Diagonals bisect each other, consecutive angles are supplementary

Parallelograms

A video about the definition and some theorems of parallelograms.

A parallelogram is a quadrilateral with opposite sides parallel.

Theorem 1: Opposite sides are congruent.

Theorem 2: Opposite angles are congruent.

Theorem 3: Diagonals bisect each other.

Four theorems are demonstrated and proven

THEOREM 8.3

If a quadrilateral is a parallelogram, then its opposite sides are congruent.

THEOREM 8.4

If a quadrilateral is a parallelogram, then its opposite angles are congruent.

THEOREM 8.5

If a quadrilateral is a parallelogram, then its consecutive angles are supplementary.

THEOREM 8.6

If a quadrilateral is a parallelogram, then its diagonals bisect each other.

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