Today was our right triangle and trig assessment day - 78 pts.
If you missed the test, please come during A&E by Thursday at the latest to make it up. Or make an appointment for another time before Thursday at 3:45.
ASPIRE testing is Wed, Feb 20. Bring a calculator if you have one (supplies are limited). We will actually begin a new unit in the short classes 1st and 2nd on Wednesday (sum of the interior angles of a polygon) with a short homework.
If I have not seen your HW #12, must see it by tomorrow!

Today was our review block. We practice area of isosceles triangles by a variety of methods, went over review in detail, practiced trig ratio word problems, shortcuts, finding point on a circle, and looked at our topic list for what is important to study.
The Unit Test (76 pts) is next block. There is a study session Friday morning at 8 am. Students could also come during A&E today.
Suggestions: rework problems you missed on the review. Now that you know how to do them, see if you can get it right. Show lots of work. Practice from any of the review worksheets that have been attached to blog posts. Answers are included. Go back and re-work problems you missed from any HW from 6 to 12. Know your shortcuts and trig ratio definitions, and how to solve any trig ratio equation (x on top, x on bottom, x is the angle).
Attached: 3 different worksheets and answers that might be helpful.
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Today our goal was to be able to use sine, cosine, and tangent ratios easily to solve problems, including missing information in stories that require a sketch.
We started with a quick warm-up: two problems over equation of circle, one over definitions of trig ratios, and one to decide if 3 lengths make a right, acute, or obtuse triangle.
We did not take a grade on HW #11, but we did go over it in detail to make sure everyone understood their mistakes and misunderstandings. I did make sure that everyone has their grades taken through HW #10. Quizzes were returned (except when I ran out of time). If you did not get your quiz back, I will return it next time. Use it as a tool to study.
We learned about angle of elevation and depression (p 590 in textbook) and did these problems in class: pp 591-2:10-13, 15-16.
Answers: 10) 655 m, 11) 101 m, 12) 65 m, 13) 188 m, 15) 1570 m, 16) a) 974 m, b) 1007 m, c) the angle would get a tiny bit bigger. All meters are approximate.
The test topics are attached below. Remember that your 80 pt assessment over Right Triangles and Trigonometry is Fri-Tues, Feb 15-19. 
Your review assignment is due Wed-Thurs, 6 pts. It is:
p 528: 1-8, 14-15, 18, 23, 25, 27-28 (only center and radius on 28) AND p 613: 1-6, 9-12, 16-18.

Today was our Right Triangle Trigonometry Day in Geometry. We started with a warm-up that used 30-60-90 relationships to lead to the ideas behind Right Triangle Trig. The lesson is on pp 655-659 in the textbook. Please read through this material and examples to help you understand if you were not here. It is actually quite good and we used part of it in class today.
I recommend getting together with a friend who was here to work on the the homework #11: p 588:1-20,22.
Synopsis from the end of class:
On problems 1-7, 11-14 just use calculator. On problems 8-10, do not use the calculator; just write ratios. On problems 15-20,22, use the examples from class and the examples from the textbook.
Quizzes will be returned on Mon-Tues. Quizzes must be taken during lunch on Monday if not already taken.
On Mon-Tues block, we will be working on using trig in real world problem solving, developing mastery of content.
On Wed-Thurs we will review the unit.
On Friday, Feb 15 and Tues, Feb 19, we will take the unit test.
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We quizzed 10.1-3 today in class. If you were absent, come during A&E and get your quiz made up this week. Friday at the latest.
Our new content today was about equation of a circle. This is discussed with examples on pp 518-19 of the textbook. Notes are attached below. HW is p 520:1-7.
We will be learning Right Triangle Trigonometry next block. Be there!
The quiz was 25 pts.
The unit test will be Fri-Tues, Feb 15-19.
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Quiz topics for next block: 

• Apply Pythagorean Theorem to find missing side. (could be diagonal of a square or vice versa).
• Apply converse to determine if right, acute or obtuse.
• Use shortcuts to find missing sides of 30-60-90 or 45-45-90  (isosceles right). Might need to keep in radical form.
• Don't forget that equilateral triangle is just two 30-60-90
• Area of triangle or square or rectangle.
• Real world application of Pythagorean Theorem.

Today our new content was about the distance formula. The notes to help with homework are attached to the post below.
Problem 14 is causing problems on HW #9: connect from origin to A' to A and back. Is this an equilateral triangle? Now connect A' altitude to the X-axis. Does this new altitude divide the triangle into 2 30-60-90's? Take it from there. (Not on a quiz or test).
HW #9 - p 512:12,14, p 517:1-3,5,7.  On the triangles in 5 & 7, you will need to use distance formula once for each side length.

I did not really finish my post yesterday, so here are some attachments that should be helpful.
You have a quiz on Tues-Wed, Feb 5-6. Topics are on the attachment with HW listed on it as well.
Also attached: notes over 3-D diagonal and rationalizing denominator; new notes over distance formula.
Attached: in-class worksheet on 30-60-90 and 45-45-90, including rationalized denominator.
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Today our new content was to rationalize denominators and to use the pythagorean theorem or shortcuts in context.
The homework #8 is p 510:1-4,6,11. Answers: 1) the bat will not fit as the diagonal is less than 34 in. 2) 10 m  3) 4 hours (remember that distance = speed times time)  4) it slides 8 ft (sketch is essential), 6) $7200   11) r = 12
A quiz on Pythagorean Theorem and the 30-60-90 and 45-45-90 shortcuts will be given on Tuesday-Wednesday next week.
Test scores on similarity will be posted tomorrow during my planning period.
Thanks for your patience.

Tests will be graded for the next block. If you have not taken the Similarity Test, you need to take it during A&E tomorrow.
Today was a big content day in Pre-AP Geometry. 
There are two big ideas that mesh together:
Right triangles (similar) with angles of 30-60-90 degrees have a predictable ratio that can be used to find missing sides: if the short leg is x, the the hypotenuse is 2x, and the long leg is x times the square root of 3. So if you know one side, you can find the other two. Isosceles right triangles (all similar) have angles of 45-45-90 degrees. If the legs of a 45-45-90 are "a" in length, then the hypotenuse is "a times the square root of 2".
We also worked at the algebra required to simplify radicals so that we can keep our answers in exact form, and so we can work better with the "Pythagorean Shortcuts" mentioned above. (2 special ratios)
In most classes, we did the "geometric model" on dot paper. And in 2 classes, we proved the Pythagorean Theorem.
HW #7 is 1-14, and 17 on the attached document PLUS pp 507-8:1-12 and 17. On the handout, copy the problem and show work. On pp 507-8, do not use the Pythagorean Theorem. Try to find the missing sides with the shortcuts (unless the triangle is not one of the special angle measures).
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Today we took the second part of the Similarity Unit Test today. If you were absent, please come ASAP to make it up. Thanks to all who have already come by!
We practiced applying Pythagorean Theorem as a warm-up. And then we covered some ground on Pythagorean Triples, using the converse to figure out if a triangle is a right triangle, etc.
 The homework due Mon-Tues is HW #6: pp 502-3:1-11,13-20. On 13-18, state whether the triangle is right, acute or obtuse. (If c squared is too big, it's obtuse.)
We also spent some time reviewing the similarity unit before we finished the test. 
Which will be graded by Monday-Tuesday block.
Get ready for Right Triangle Unit!!