Tuesday 8/13/13 Geometry


Recap Developing Definitions INB 19 from yesterday.  Ensuring we discuss the appropriate notation of terms.


In class, we partnered and played Blind Draw INB 16.  You had to choose a card containing one of the above figures, then give instructions to your partner and they tried to replicate it based solely on your directions.  If you were absent, choose 3 pictures and write your verbal directions on INB 16.

HW assignment:
1. write a reflection about the activity, tell what was hardest & easiest, why, for both roles of giving and receiving instructions.

2.  Create your own sketch, incorporating at least 1 point, 1 line, 1 plane and at least one other vocabulary term.  Include appropriate notations.  Cover your sketch with a post-it. 

Write directions for your sketch.  I will give you feedback based on how closely I can draw your sketch using your directions.

INB 18  Draw What I Say 

This page was similar to page 18, but is more scripted.  The focus is correct notation. 

If you need a copy to complete the assignment please email me.

Have a parent or friend read the instructions and you draw the figures onto INB page 18. When complete, check your drawing against the answer on  the card.  Write a short reflection, what did you do well on, what do you need to improve?

Patty Paper exploration…

Use a straightedge to draw a segment with endpoints CD. 


Fold C to D and crease your paper.


Unfold your paper.


What do you see?  notice? 

Label the point where the crease intersects CD, E.


How does CE compare to DE?  What does this tell you?

Compare the 4 angles formed…if I fold along thencrease, then fold along the segment, the 4 angles are congruent…90º.


So that means, j is a perpendicular bisector of CD.


Place a point, F, on j above CD.  Connect CF and DF with  straightedge.  What do you notice?

Place another point, G, on j above CD.  Connect CG and DG with a straightedge. What do you notice?

Place another point, H, on j below CD.  Connect CH and DH.  What do you notice?

Will this always be true?


Geometry 1/9/13

INB 15 Segments & Midpoints


INB 14 Part 1 Processing Midpoints of Segments (boss/secretary) Part 2 Segment Addition practice page 8


INB 17 Midpoints with Coordinates


After some sharing of how to find the midpoints with graph paper – another student suggested he added the coordinates, then divided by 2. 

Find M, the midpoint of AB.  A(7, 3) and B (13, 5)…

x-coordinates:  7+13=20 / 2 = 10 and y-coordinates:  3 + 5 = 8 / 2 = 4 so the midopint will be M(10, 4)

INB 16 practice #11-20


Several of the practice suggestions are from iXL – I just learned about this at a math leadership meeting this week as well as it was suggested by a couple of parents on Friday (THANK YOU!).  You may do up to 20 practice problems per day without having an iXL account.

When a problem is incorrect, it gives the correct answer AND an explanation/practice for you to “get it”.  I see this site a great benefit to use throughout a unit of study.

For most topics, I have linked to the Open Math Reference site which offers not only text but also interactive examples of each.


Classifying Triangles – Sides, Angles

Interior Angle Sum

Exterior Angles

iXL practice on the above go here  and see F1, F2, F3

Using Converse of Pythagorean Theorem to Classify Triangles  (Triangle Type Quiz

iXL practice see Q1, Q2, Q3

Triangle Inequality

Relationships sides / angle

Isosceles Triangles

Equilateral Triangles

Special Lines/Segments of Trianlges:

Midsegment of Triangle

Medians, Angle Bisectors, Altitudes, Perpendicular Bisectors

iXL practice on the above see M1, M2, M3

Triangle Centers

Triangle Congruence –  Triangles are congruent if you can slide them around, rotate them, and
flip them over in various ways but can “pile” on top of one another.

AAS – if 2 angles are known to be congruent in a triangles and a side OPPOSITE one of those angles is congruent.
HL – MUST know the triangle is a right triangle
SSA – the one that shall not be named…does not guarantee congruence!
AAA – does not guarantee congruence but does prove similarity,
iXL practice see K1, K2, K3, K4, K5

Geometry Target Quizzes & Midsegment Investigation

TQ1Classify INB 23

 TQ2ConversePT  (Classify Triangle Investigation…highlight acute, right, obtuse…)

TQ3ExteriorAngleSums INB 23

TQ4TriangleInequality INB 25 (straw activity)

Midsegment Investigation– completed by Wednesday – if you are not recognizing any patterns in the chart – please go back and check your slope & distance calculations!  Some silly mistakes  can cause all of your conclusions to be incorrect~!