Thursday October 17 Math Message Label unit 39 and the date at the top of your Math Response Complete the following in your Math Notebook Using a straightedge draw a big triangle in your notebook ID: 497700
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Slide1
3.9 Angles of Polygons
Thursday, October 17Slide2
Math Message
Label unit 3.9 and the date at the top of your Math Response
Complete the following in your Math Notebook:
Using a straightedge, draw a big triangle in your notebook
Measure
its angles (with the full circle or half circle protractor)
Then
find the sum
.
B
e prepared to share this answer in class on our line plotSlide3
Finding the sum of angles in a triangle
If a triangle is accurately drawn and the angles are measured with precision,
the sum of the angles will always be 180 degrees
When placed together along a straight line, the angles will form a
straight angle
, which is always 180 degreesSlide4
Finding the sums of angles in polygons
Convex Polygon
The interior angles are less than 180 degrees
Concave Polygon
At least one interior angle is greater than 180 degrees. This angle is also called the reflex angleSlide5
Polygons Activity in class
The following activity will be completed in class:
Polygons
Not Polygons
Convex Polygons
Concave PolygonsSlide6
Quadrangles & Quadrilaterals
http://studyjams.scholastic.com/studyjams/jams/math/geometry/classify-quadrilaterals.htmSlide7
Class discussion: Why do you think the medians for the sums of polygon angles increase by 180 degrees?
Because the sum of a triangle is 180 degrees, each triangle you are able to fit in the polygon shape will then increase the sum by 180 degrees.
Sum of the angles of a triangle = 180 degrees
Sum of the angles of a quadrangle = 360 degrees
(Quadrangles divide into 2 triangles;
2 * 180 = 360 degrees)
Sum of the angles of a pentagon = 540 degrees ( 3 * 180 = 540 degrees)Sum of the angles of a hexagon = 720 degrees
( 4 * 180 = 720 degrees)Slide8
3.10 Solving Problems Using the Geometry Template
Monday, October 21Slide9
Math Message
Label unit 3.10 and the date at the top of your Math Response
Answer the following question in your Math notebook:
Choose any
3 components
of your Geometry Template and
explain the importance of each one
.
1) example: T4 (isosceles triangle)- this triangle can be traced out and used to show what an isosceles triangle would look like
2)3)Slide10
Drawing circles with the Geometry Template
This activity will be completed in class.
Place the Geometry Template on your Math Notebook page
Put one pencil in the circle guide (hole) at 0 inches and another pencil in the circle guide at 3 inches.
Use the pencil at the 0-inch mark as an anchor (like the anchor on a compass) while you scribe a circle around it with the pencil at the 3-inch mark.
This circle shows a diameter of 6 inches. Slide11
Unit 3 Review
Tuesday, October 22 Slide12
Skills students will be assessed on…
Identify place value digits in numbers to billions
Identify right, straight, reflex, obtuse, and acute angles
Use a protractor to measure angles
Identify right, isosceles, equilateral, and scalene triangles
Use the Geometry Template to draw right, isosceles, equilateral, and scalene triangles
Identify polygons
Make patterns that tessellate