Circle I TEST

TEST Tomorrow! 

Test Specs:
Definitions  16 pts
Circumference  9 pts
Applicaions of Theorem  75 pts
(finding arc / angle measurements)

Check your answers to the review assignment from the Homework page at….
http://www.shelbyed.k12.al.us/schools/omhs/faculty/sculbreth/hmwrk.htm

I’ll check the GeoBlog @ 8:30 and 10:00 tonight.
So, post your questions/problems and I’ll respond.
I’ll be available @ 7:00 Wednesday morning in the classroom.

STUDY!
Mrs. C

Arcs and Angles (1-5)

              central angle2.JPGcentral angle 1 = intercepted angle XY(shown in red) *central angle-vertex on center of circle and radii are its legs

**Ex.- if angle 1=107, arc XY=?       107

 

inscribed angle.JPGinscribed angle 2= 1/2 intercepted arc AB(in purple and red) *inscribed angle- vertex on circle and chords are its legs

**Ex.-if arc AB=240, angle 2=?       120

 

same angleinscribed angle 3= inscribed angle 4 OR angles inscribed in same arc are congruent (in red and green)

**Ex.- if angle 3=47, angle 4=? arc CD=?       47;94

 

semicircleangle 5=90  OR if an angle is inscribed in a semicirclethen it is a right angle

**Ex.-if GI is a semicircle, angle 5=?     90

 

quadangle 6+angle 9=180   angle 7+angle 8=180    OR   oppisite angles of an inscribed quadrilateral are supplementary

**Ex-if angle 8= 127, angle 6=88, angle 7=? angle 9=?    53;92

       Using the theorems above find the following angles and arcs:

practice

arc AB;DC;DE;AE                  angles 2;3;4;5;6

if arc BC=70 and angle 1=30

 answersangle 1=30 angle2=55 angle3=35 angle4=55 angle5=35 angle6=70

arc AB=110 BC=70 CD=80 DE=30 EA=70

-Jennifer L.

Arcs and Angles (6-10)

6. The measure of an interior angle, formed by two chords, is equal to 1/2 the sum of the intercepted arcs.

ex. angle 2 intercepts arc NM {= 120 degrees} and its vertical angle, angle 1, intercepts arc KL{=50 degrees}. Therefore [arc NM +arc KL ]/ 2 = angle 2 [or angle 1] ….[120+50]/ 2 = 85 degrees.
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7. The measure of an exterior angle formed by two secants is equal to 1/2 the distance of the difference of the two intercepted arcs.

ex. angle 1 intercepts arc PO{=130 degrees} and arc QR{=20 degrees}. Therefore [arc PO- arc QR]/ 2 = angle 1… [130-20]/ 2= 55 degrees.

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8. The measure of an exterior angle formed by a secant and a tangent is equal to 1/2 the distance of the difference of the intercepted arcs.

ex. angle 1 intercepts arc TW{=140 degrees} and arc UW{=60 degrees}. Therefore [arc TW- arc UW]/ 2 = angle 1… [140-60]/ 2= 40 degrees.

—————————————————————————————–

9. The measure of an angle formed by a tangent and a secant to the point of tangency is equal to 1/2 of the single intercepted arc.

ex. angle 1 intercepts arc VX{=110 degrees}. Therefore [arc VX]/ 2 = angle 1…[110]/ 2 = 55 degrees.

—————————————————————————————–

10. The measure of an exterior angle formed by two tangents is equal to 1/2 the difference of the intercepted arcs.

ex. angle 1 intercepts arc YAZ{150 degrees} and arc YZ{30 degrees}. Therefore [arc YAZ- arc YZ]/ 2 = angle 1… [150-30]/ 2= 60 degrees.

-Kiersten V.

GeoBlog Analysis

Please take a few minutes to reply…..Your responses will help me to improve GeoBlogs!  I want this to be the best possible tool to help YOU in Honors Geometry!!
I’m proud of those who bravely scribed – some blogging for the first time!!  I hope to avoid the technical difficulties we experienced by allowing you to actually post this Nine Weeks and not just “reply”. 

What do you think about GeoBlogs???
Did blogging help facilitate your learning during the 3rd Nine Weeks?
When you were the scribe, did it affect your focus in class?
What is the BEST thing about blogging for academics?
What is the WORST thing about blogging for academics?
How would you change GeoBlog to make it better?

(Let’s suspend the “first name/last initial” rule for this post.  You may just be Student or Anonymous.  I want you to be honest!! It won’t hurt my feelings – You all know that high school teachers don’t have feeling!!)  )

Thanks!
Mrs. C

Polygon / Polyhedron TEST

TEST Tomorrow! 

Test Specs:
Matching w/ definitions & pictures  22 pts
Apply Euler’s Law  12 pts
Platonic Solids  18 pts
Polygon Chart  33 pts
Apply perimeter / angle measures  15 pts

Your review sheet today listed the formulas that you need to know….KNOW your formulas!!

I’ll check the GeoBlog @ 8:30 and 10:00 tonight.
So, post your questions/problems and I’ll respond.
I’ll be available @ 7:00 Wednesday morning in the classroom.

STUDY!
Mrs. C

Angles / Diagonals in Polygons

Date:  3/9/06
Objective:  Derive and apply formula for finding interior and exterior angle measurements in polygons.  Derive and apply formula for finding diagonals from 1 pt and total diagonals.

Sorry I’m late!  The bad weather made me leave school sooner than I anticipated.  And once I got home…..dinner was #1 priority for the Culbreth family! 🙂

Coordinate Geo w/Quads & Trapezoids TEST

TEST Tomorrow! 

Test Specs:
Verify w/ specific method   3 questions
Verify w/ your choice of method   4 questions
Algebra Apps w/ trapezoids   3 questions
Determine type of quad & explain with complete sentences   4 questions

If you can work the problems from the Review Sheet, you will do GREAT on the test.  The answers to the review are posted on the Homework page of my website
http://www.shelbyed.k12.al.us/schools/omhs/faculty/sculbreth/hmwrk.htm

Remember, you only have to choose one method to verify.  Be careful with your explanations!  “Slopes are equal.” is NOT enough.  I need you to tell me, “Slopes are equal, therefore the lines are parallel.”

I will check the GeoBlog tonight at 8:30 and 10:00. 
(I may be a little late for the 8:30, but will be there ASAP!) 
Post any questions or problems. 

No morning study session tomorrow (Wed).  Sorry!!  I have a 7:00 meeting.
The Review Sheet and the key to your graded assignment will be posted outside my door.

One last reminder…..
Time management will be essential for this test.  Be prepared to start as soon as the bell rings and watch your time carefully.  Don’t spend too long on any one question.

STUDY!
Mrs. C