Mcdougal Littel Geometry Chapter 5 Theorums

Front 1

5-1

Back 1

Opposite sides of a parallelogram are congruent.

Front 2

5-2

Back 2

Opposite angles of a parallelogram are congruent.

Front 3

5-3

Back 3

Diagonals of a parallelogram bisect each other.

Front 4

5-4

Back 4

If both pairs of opposite sides of a quadrilateral are congruent, then the quadrilateral is a parallelogram.

Front 5

5-5

Back 5

If one pair of opposite sides of a quadrilateral are congruent, then the quadrilateral is a parallelogram.

Front 6

5-6

Back 6

If both pairs of opposite angles of a quadrilateral are congruent, then the quadrilateral is a parallelogram.

Front 7

5-7

Back 7

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

Front 8

5-8

Back 8

If two lines are parallel, then all points on one line are equidistant from the other line.

Front 9

5-9

Back 9

If three parallel lines cut off congruent segments on one transversal, then they cut off congruent segments on every transversal.

Front 10

5-10

Back 10

A line that contains the midpoint of one side of a triangle and is parallel to another side passes through the midpoint of the third side.

Front 11

5-11

Back 11

The segment that joins the midpoints of two sides of a triangle
1) is parallel to the third side;
2) is half as long as the third side.

Front 12

5-12

Back 12

The diagonals of a rectangle are congruent.

Front 13

5-13

Back 13

The diagonals of a rhombus are perpendicular.

Front 14

5-14

Back 14

Each diagonal of a rhombus bisects two angles of a rhombus.

Front 15

5-15

Back 15

The midpoint of the hypotenuse of a right triangle is equidistant from the three vertices.

Front 16

5-16

Back 16

If an angle of a parallelogram is a right angle, then the parallelogram is a rectangle.

Front 17

5-17

Back 17

If two consecutive sides of a parallelogram are congruent, then the parallelogram is a rhombus.

Front 18

5-18

Back 18

Base angles of an isosceles trapezoid are congruent.

Front 19

5-19

Back 19

The median of a trapezoid
1) is parallel to the bases;
2) has a length equal to the average of the base lengths.