MJ2A

Ch 10.4 - Quadrilaterals

Bellwork

• Identify each transformation as a reflection, rotation or translation:

1. 2. 3.

Assignment Review

• Text p. 510 # 7 – 13

Before we begin…

• Please take out your notebook and get ready to work…

• Yesterday we looked at transformations on the coordinate plane…we will continue with the geometric theme today by looking at quadrilaterals….

Objective

• Students will classify quadrilaterals and find missing angle measurements.

What is a Quadrilateral?

• Raise you hand if you can tell what a quadrilateral is….

Quadrilaterals

• Quadrilaterals are closed four sided figures with four vertices.

• The prefix Quad means four…

• The line segments that make up quadrilaterals intersect only at their endpoints.

Examples of Quadrilaterals

• Are Quadrilaterals:

• Are NOT Quadrilaterals:

Finding Missing Measures

• In a Quadrilateral the sum of the angle measurements equals 360°

• To find a missing measure add up the given measurements and subtract from 360°

• Lets look at an example…

Example

• In the example to find the measure of angle x add all the other angles and subtract from 360°

62 + 88 + 2x + x = 360150 + 2x + x = 360150 + 3x = 360-150 -150 3x = 210 3 3 x = 70Therefore, D = 70° and

C = 140°

62°

88°

2x°

x°A

B

C

D

Your Turn

• In the notes section of your notebook draw and label the quadrilateral, find the value of x. Then find each missing angle measurement.

4x°

75°

110°

x°Q

R S

T

Classifying Quadrilaterals

• When classifying quadrilaterals the description that is most specific is what is used.

• Let’s see what that looks like…

Classifying Quadrilaterals

Quadrilateral

Trapezoid

Parallelogram

Rectangle

Square

Rhombus

Summary

• In the notes section of your notebook summarize the key concepts covered in today’s lesson

• Today we discussed– Finding the missing measure of quadrilaterals

– how do you do that?– Classifying Quadrilaterals – how do you

classify them?

Assignment

• Your assignment is to create a quadrilateral map…I will provide you with the format.

• You are to Identify each quadrilateral and the characteristics of each.

• You may use text p. 514 to help you…however you should already know most of this material….

• This assignment is due tomorrow!