# Math 6.4

## 13 terms · McDougal Littel Geometry

### Rhombus

a parallelogram with four congruent sides

### Rectangle

a parallelogram with four right angles

### Square

a parallelogram with four congruent sides and four right angles (combination of a rhombus and a rectangle)

### Rhombus Theorems

(1) a parallelogram is a rhombus if and only if its diagonals are perpendicular (2) A parallelogram is a rhombus is a rhombus if and only if each diagonal bisects a pair of opposite angles

### Rectangle Theorems

(1) A parallelogram is a rectangle if and only if its diagonal are congruent

### Trapezoid

a quadrilateral with exactly one pair of parallel sides

### Trapezoid's bases

the parallel side

### Trapezoid's legs

the nonparallel sides

### isosceles trapezoid

the legs of the trapezoid are congruent

### Isosceles trapezoid Theorems

(1) a trapezoid is isosceles, then each pair of base angles congruent (2) Atrapezoid is isosceles if and only if its diagonals are congruent

### Mid segment theorem for Trapezoids

The midsegment og a trapazoid is parallel to each base and its length is one half the sum of the lengths of the bases

### Kite

a quadrilateral that has two pairs of consecutive congruent sides

### Kite Theorems

(1) a quadrilateral is a kite, then its diagonals are perpendicular (2) If a quadrilatrilateral is a kite, then exactly one pair of opposite angles are congruent