Hi, my name is Marie.  I am currently enrolled in community college.  I am taking a math class this semester.  This math class's goal is to help prepare us students to become future teachers.  My teacher, assigned us the task of making a blog.  I have never done a blog before, but I hope that this blog will be amazing.  I hope to instill in everyone that reads how much I love teaching.  I have volunteered my time in Elementary schools for three years now.  I have since, completed more than one hundred hours.  I love kids.  This blog will be geared towards all ages to help everyone learn the basics of geometry.

  In this blog I will discuss six topics.  One, I will help you distinguish shapes such as a parallelogram, rhombus, etc.  Two, I will explain the different types of triangles as well as the basics of triangles and how to find their missing angles.  Three, I will help show you how to add and subtract things like 18 degrees, 35', and 29" + 22 degrees, 55', and 41".  Four, I will help show you the difference between concave and convex.  Five, I will help explain corresponding angles as well as other angles.  Six, I will help you find the length of a particular shapes sides.

  By the end of the blog, I hope I have helped instill a love for geometry in everyone who read.  I had a terrible geometry experience and I'd never want anyone to have trouble like I did.  LOVE GEOMETRY!  Because Geometry opens you up to things you see in everyday life.  There are shapes all around you and angles!  Your probably sitting at a laptop or computer.  What shape is it?  That's geometry!  Love it!  Don't fear it.  I'm here to help!

Links for Fast searches:

Shapes 
Triangles
Adding Hours, Minutes, Seconds
Concave vs. Convex
Angles Including Corresponding Angles
Interior and Exterior Angles
Thanks for Reading and My Favorite Blogs

  First, I am going to help you all learn your shapes.  I asked you in my first post what shape your computer or laptop was.

This ones an easy one.  Your computer looks like this doesn't it?

This shape is a rectangle.  We all know this one hopefully.  Let's look at some more shapes in geometry.

See how many shapes we have?  It might help to ask yourself how many shapes you can find, like the ones above, in your house.  You might say that an octagon looks like a stop sign.

Or that a clock looks like a circle.

Feel free to post comments of the different shapes you find your home :)  I would love to hear from you all.

Now that you know the shapes you know the basics of geometry.  We will now discuss some of them in more detail starting with the triangle.

  Now let's look at triangles.
  How many sides does a triangle have.... 3 right?

However,  there are many different types of triangles...
Here are the definitions of each...  (click on the image to enlarge)

  A triangle has three sides and three angles.

All of the angles add up to 180 degrees.  Here is an example...

45°+90°+45°= 180°
Note:  ° means degrees

What if you were given an equation like this?

One can see we have 85° and 55°.  We do not have x.

To find x you need to first add up these two numbers
85°+55°= 140°

All triangles equal 180° total :)
So...

Take the 140° and minus it from 180°
180°-140°= 40°

The ANSWER:  X= 40°

Now I will show you how to add and subtract things like 

18°, 35', and 29" + 22°, 55', and 41".  

The degrees (°) will represent hours, the ' will represent minutes, and the " seconds.  (It looks hard, but trust me once you catch on you can do it in your sleep :) just stick with me and YOU WILL BE OK!)


     18°, 35', and 29"
 +  22°, 55', and 41".  
-------------------------
    40°  90'   and  70"              I just added these like normal numbers.  

                                             It reads 40 hours, 90 minutes 70   seconds.  This isn't pretty to look at.  We
                                            should never have more than 60 minutes or 60 seconds because 
                                            60 minutes= 1 hour and 60 seconds=1 minute.  
                                           We need to rearrange a couple things
   ---------------------- 
   41°  30'   and  70"       
                                            Here, I took the 90'-60' (90 minutes minus 60 minutes (which equals one hour)
                                            to make it look nicer.  Because 60 minutes= 1 hour.  So 90'-60= 30' (minutes).
                                            I told you that I took 60 minutes from the minutes ' which equals one hour
                                             So I added 40°+1° or 40 hours+ 1 hour from the minutes we used to equal
                                             41 hours.  We still have one number higher than 60 which is 70" (seconds).

41 hours,  30 minutes,  70 seconds
41°            30'              70"
-------------------------------

41°            31'              10"            THIS IS YOUR ANSWER

 (OR 41 hours, 31 minutes, and 10 seconds)
How did I find this answer?  Well I told you that 70 seconds is over 60.  So we need to take the 70" (seconds) and minus 60 from it (70"-60"=10).  Then since we took 60 seconds away 60 seconds=1 minute so we add a minute.  30' (minutes) + 1' (minute)=  31 minutes.

With a little practice you too can become a pro!  Subtraction is easier.  Let's take a look...

  15°  29'
-  3°  45'
------------    First can you minus 29 from 45?  No you cant.  So you need to borrow from the 15.
                      Make the 15° (hours) 14° (hours).  1 hour=60 seconds so add 60' to 29'
                      60' (minutes)+ 29' (minutes)= 89'  We now have something like this...

  14°  89'
-  3°  45'
--------------  Now it's just simple subtraction to get your answer

ANSWER:  11°  44' (or 11 hours and 44 minutes)

CONCAVE VS. CONVEX

As you can see concave shapes have a place that slopes inwards almost like a hole in the shape.  Convex shapes are complete with no holes.

See the difference?

Contact lenses can be an example of concave and convex.

If you see a shape slope inwards at any degree the probability of it being concave increases.  See the slope in the concave angle.  It's almost like you could draw a dotted line from the top to the bottom to make it a real shape (rectangle).  The oval is complete with no gaps and we could not draw a dotted line from the top to the bottom and have empty space.


Here is a trick question.  Is this heart concave or convex?

It's Concave!
 Why?  Because if you draw a line from one curve of the heart to the other you can find empty space or gaps between the two curves.

Angels including Corresponding Angles

This is the chart you will most likely see when asked to find certain angles such as, corresponding angles, in geometry.

 This is a fun video song that will help you learn all the angles including corresponding angles!  

Background knowledge.  A parallelogram shapes angles=360.

110° + 70° + 70° + 110° = 360°


:D I hope you enjoy it.
It's much more fun and I think it does an amazing job explaining it.

Finding Interior Angles

I will now help you find the interior angles of a particular shapes through the formula n (or the number of sides the shape has)-2(180) to find the length of sides take the answer and divide it by n (again the number of sides).

The person making this video goes a bit fast so I will explain it more in depth and then your welcome to watch the video.  I apologize for the low quality sound.

 He is looking at a pentagon.

A pentagon has five angles or points.  Count the edges to find out there are five.  Five edges means five angles.

So lets look at our formula n-2(180
n= the number of sides a pentagon has

We counted the angles so we know the pentagon has five sides so plug 5 in for n
5-2(180) 
3(180)

= 540°  (REMEMBER ONLY A PARALLELOGRAMS ANGLES/SIDES ADD UP TO 360°)

To find all the interior angles individually you need to take
540/n
n= the number of sides or 5 for the pentagon
540/5=  108° each

 To find an exterior angle you take your answer and minus it from 180° (YOU WILL SEE THIS IN THE VIDEO).  He extends lines from each side/point of the pentagon to find each exterior angle.

180° - 108° = 72°

He has one more example of a hexagon afterwards that I will leave for you to try with him and on your own.  If you have any questions feel free to comment.