6-4 To 6-6

Front 1

rectangle

Back 1

a quadrilateral with four right angles

Front 2

theorem 6-4-1

Back 2

if a quad. is a rectangle, then it is a parallelogram

Front 3

theorem 6-4-2

Back 3

if a parallelogram is a rectangle, then its diagonals are congruent

Front 4

theorem 6-4-3

Back 4

if a quad is a rhombus, then it is a parallelogram

Front 5

theorem 6-4-4

Back 5

if a parallelogram is a rhombus then its diagonals are perpendicular

Front 6

theorem 6-4-5

Back 6

if a parallelogram is a rhombus, then each diagonal bisects a pair of opposite angles

Front 7

rhombus

Back 7

a quadrilateral with four congruent sides

Front 8

square

Back 8

quadrilateral with four right angles and four congruent sides

Front 9

theorem 6-5-1

Back 9

if one angle of a parallelogram is a right angle, then the parallelogram is a rectangle

Front 10

theorem 6-5-2

Back 10

if the diagonals of a parallelogram are congruent, then the parallelogram is a rectangle

Front 11

theorem 6-5-3

Back 11

if one pair of consecutive sides of a parallelogram are congruent, then the parallelogram is a rhombus

Front 12

theorem 6-5-4

Back 12

if the diagonals of a parallelogram are perpendicular, then the parallelogram is a rhombus

Front 13

theorem 6-5-5

Back 13

if one diagonal of a parallelogram bisects a pair of opposite angles, then the parallelogram is a rhombus

Front 14

kite

Back 14

quad. with exactly two pairs of congruent consecutive sides

Front 15

theorem 6-6-1

Back 15

if a quad. is a kite then its diagonal are perpendicular

Front 16

theorem 6-6-2

Back 16

if a quad. is a kite, then exactly one pair of opposite angles are congruent

Front 17

trapezoid

Back 17

quad. with exactly one pair of parallel sides

Front 18

base

Back 18

each of the parallel sides

Front 19

legs

Back 19

the nonparallel sides

Front 20

base angles

Back 20

two consecutive angles whose common side is a base

Front 21

isosceles trapezoid

Back 21

the legs of a trap are congruent

Front 22

theorem 6-6-3

Back 22

if a quad.is an isosceles trapezoid then each pair of base angles are congruent

Front 23

theorem 6-6-4

Back 23

if a trapezoid has one pair of congruent base angles, then the trapezoid is isosceles

Front 24

theorem 6-6-5

Back 24

a trapezoid is isosceles if and only if its diagonals are congruent

Front 25

midsegment of a trapezoid

Back 25

segment whose endpoints are the midpoints of the legs