Quadrilaterals

Diagonals

a line segment that connects 2, non-consecutive vertices

Kite

 its four sides can be grouped into 2 sets of equal sides that are adjacent to each other

Parallelogram

- two sets of opposite sides are parallel

Rhombus

a parallelogram with 4 congruent sides

 

Rectangle

a parallelogram with 4, 90 degree angles

Square -

a parallelogram that is a rhombus and a rectangle

Area of a Parallelogram, Rectangle, or Square

 A = bh

Area of a Rhombus or Kite

 A = ½ d₁d₂

Area of a Triangle

Area of a Triangle

Area of a Trapezoid

 A = ½ h (b₁ + b₂)

In a Regular Polygon, the Relationship Between One Interior and One Exterior Angle that are Adjacent

interior angle + exterior angle = 180

In a Regular Polygon, the Sum of the Exterior Angles

(exterior angle)(number of sides) = 360

In a Regular Polygon, the Sum of the Interior Angles

S = 180(number of sides - 2)