Unit 6: Relationships in Polygons

Unit 6 Learning Targets 

LT 6-1: I can use the Polygon Sum conjecture to find missing measures.

LT6-2: I can use the Exterior Angle conjecture to find missing measures.

LT6-3: I can use the properties of Kites and Trapezoids to find missing measures.

LT6-4: I can use the properties of Parallelograms to find missing measures.

LESSON 6-1

The Polygon Angle-Sum Theorems

The sum of the exterior angles of a polygon is 360°, regardless of the number of sides. The sum of the interior angles of a polygon is 

180°(n-2), where n is the number of sides.

Help Videos:

●       How Do You Find the Sum of the Interior Angles of a Polygon?

●       Why Is the Sum of the Exterior Angles of a Polygon Always Equal to 360°?

Practice:

6-1 Math XL

LESSON 6-2

Kites and Trapezoids

Diagonals of a kite are perpendicular, and one diagonal bisects the other. In isosceles trapezoids, diagonals are congruent. The length of the midsegment of a trapezoid is half the sum of the base lengths.

Help Videos:

●     How Do You Find a Value for a Variable in a Trapezoid? 

Practice:

6-2 Math XL

LESSON 6-3

Properties of Parallelograms

In a parallelogram, consecutive angles are supplementary, opposite angles are congruent, opposite sides are congruent, and diagonals bisect each other.

Help Videos:

●    How Do You Find Values for Variables in the Angles of a Quadrilateral to Make It a Parallelogram? 

Practice:

6-3 Math XL

LESSON 6-4

Properties of Special Parallelograms

The diagonals of a rhombus are perpendicular, bisect each other, and bisect opposite angles. They form four congruent triangles. In a rectangle, the diagonals are congruent. Squares have properties of rhombuses and rectangles.

Help Videos:

●       How Do You Use Variables to Name Coordinates for a Figure Placed on the Coordinate Plane?

●       How Do You Find the Value for a Variable in the Angles of a Quadrilateral to Make It a Rhombus?

●       How Do You Use the Diagonals of a Rectangle to Find the Value of a Variable? 

Practice:

6-4 Math XL

Unit 6 Vocabulary

●       midsegment of a trapezoid