# 6.2

## Theorem 6-1

Opposite sides of a parallelogram are congruent

## Theorem 6-2

Opposite angles of a parallelogram are congruent

## Theorem 6-3

The diagonals of a parallelogram bisect each other

## Theorem 6-4

If three (or more) parallel lines cut of congruent segments on one transversal, then they cut off congruent segments on every transversal

## Example Theroem 1

180-53= x

127= x

The angle opposite of the angle with 53 degrees, is 53 degrees. The missing angle, x, is 127, and so is the angle opposite of it.

## Example Theorem 2

3x + 2 = 14

3x = 12

X = 4

3(4) + 2 = 14

## Example Theorem 3

Number 18

PT= x + 2 and TR= y

QT= 2x and TS= y + 3

x + 2 = y

2x = X + 2 + 3

X = 5

(5) + 2 = y

Y= 7