Our homework is to make an account on del.icio.us and find 1 site for each unit we have studied so far using Firefox. del.icio.us allows you to save bookmarks which you are able to access from any computer no matter where you are.

**This is how to do it:**

- Open up firefox

- Type del.icio.us in the address box

- Click register

- Click install extension now

- Restart Firefox

- Go to help and click bookmarklet buttons for any browser

- Drag the post to del.icio.us button to where your tabs (beside latest headlines)

- Find 1 site for each unit that we have done so far

- To bookmark a site, click the tag button on your toolbar and save it

- Find a site for each unit we studied and bookmark it with pc30sf06 as one of the tags

Another thing to check out is http://k12onlineconference.org and go to

**Basic/Advanced Thinking**scroll down to the second last post which is posted by

**Alan Levine**. This shows you different education tools and how to use them.

We also started a new unit today called Analytic Geometry we started off with a diagram:

From this diagram you can pull out this information:

OP = r

You can change the distance formula which is

^{2}+ (y-k)

^{2}

Standard form for the equation of a cirlcle is (x-h)

^{2}+

(y-k)

^{2}= r

^{2}

If the coordinates for the center point of the circle was (2,color=blue>-1) the formula would be:

(x-2)

^{2}+ (y-(-)1)

^{2}= 9 and the radius would equal the square root of 9

which is 3

The graph for this formula would look like this:

So if you know (h,k) and the center point of a circle, you can write the equation of the circle.

Eg. If the coordinates of the center point is (-3,4) and the radius is 5 this is what you do:

**substitute**them in: (x+3)

^{2}+ (y-4)

^{2}= 25

******be careful with the signs

then you

**expand**: x

^{2}-4x+4+y

^{2}+2y+1= 5

after that,

**simplify**: x

^{2}+y

^{2}-4x+2y+1=0 which is the general

form

when you finish simplifying, complete the square: x

^{2}-4x+4+y

^{2}+2y+1=0+4+1

(x-2)

^{2}+(y+1)

^{2}= 5 and this becomes the

__original__

equationequation

*****you get +4 by taking half of -4 from "-4x" which is -2 and squaring it +1 by taking half of the 2 from "2y" and squaring it.

**[ ! ]**If you are ever given the diameter, remember that the radius is half of the diameter

Homework is not only creating an account for del.icio.us,

**is also for homework OH.. AND THE SCRIBE FOR TOMORROW IS**

__Exercise 21__**eeDce**:)

Crysta nice post. It would be helpful if the links were live. Just highlite what you want to be the link and use the link button on the buttonbar.

ReplyDeletethanks for scribing

Mr. Harbeck

Sargent Park School