Monday, November 30, 2009

Area of a Triangle


Area of Triangles


Triangle - A three sided figure
- has three angles
eg.




Because a triangle is half of a square, rectangle, or a parallelogram the formula to find a triangle's area is (bxh) divided by 2.













Practise



1. Find the area of triangle ABC


bxh divided by 2 = area of triangle

4x7 divided by 2 = a
28 divided by 2 = a

14 cm squared = area and answer



2.


bxh divided by 2 = area of triangle

4x6.5 divided by 2 = a

13 cm squared = area and answer



3.
bxh divided by 2 = area of triangle
10.5 x 8 divided by 2 = 84
84 divided by 2 = 42
42 mm squared = area and answer
Here is a link that can help you as well.



This is a video that can help you.




Monday, November 23, 2009

Angle Bisectors

Angles
-The space between 2 connecting lines

















Acute

-An angle that is less than 90o.













Obtuse

-An angle that is greater than 90o and less than 180o.














Right A
ngles
-Are angles that are exactly 90o.












Straight Angles

-Are angles that are exactly 180o.













Angle Bisector

-The line that divides an angle into two equal parts.
[Equal angles are marked with the same symbol, O.]





















Method 1 to make an Angle Bisector:
Fold paper.






Method 2 to make an Angle Bisector:

Get a compass and make an arc (angle for this step) from the vertex that crosses both arms. Label them X, Y. Then make another arc but from X, Y. They must be the same distance from its point, and have to be intersecting. Now when your done that, draw a dotted line down the X,Y's arc intersection. That is your Angle Bisector. It should look like this.


















Method 3 to make an Angle Bisector:

Grab a protractor. An <>140o. Divide your angle measurement by 2. 140o/2=70o. (There are more steps, but I missed them, and I do not have the proper diagram drawn. I apologize, but i hope you have an idea for what to do next.







HOMEWORK

1. Make a 68o angle. Then draw the angle bisector using two methods.


2. How could you divide an angle into four equal parts?

3. Has each angle been bisected? How do you know?




























Sorry I missed some parts. If I did, be sure to comment on this and tell me.

Hope this was helpful!

Wednesday, November 18, 2009

Geometry

Parallel - describes lines in the same place that never cross or intersect.
- they are marked using arrows.

Perpendicular - describes lines that intersect at right angles (90degrees)
- they are marked using a small arrow.

measure the distance from: A to B = 8.9 cm B to C = 8.9 cm
E to F = 8.9 cm F to G = 8.9 cm
I to J = 8.9 cm J to K = 8.9 cm

Identify any parallel line segment line:

AE is parallel to BF
BF is parallel to CG
EI is parallel to FJ
FJ is parallel to GK
AI is parallel to CK

Parallel lines are always the same distance apart. No matter where you measure as long as you measure using perpendicular lines.

Now using the same picture ^, identify any perpendicular line segments.
AE is perpendicular to DF
BF is perpendicular to EG
CG is perpendicular to FH

1. Are line segments AE and DF parallel?
2. Are line segments DF and BE perpendicular?
3. Are line segments AC and BG perpendicular?
How do you know?
4. Would a line segment joining A to D be parallel to a line segment BE?
How do you know?





Three Ways To Make Perpendicular Lines


The first way of making bisect perpendicular lines.



1.Draw a line segment on a piece of paper.















2.Make the ends of the line segment point A and point B.



3.Fold the paper so point A is exactly on top of point B.



4.Draw a line down the crease that you have made.


5. Now you can input your right angle in the top right box or the bottom left.


The second way of making bisect perpendicular lines.


1.Using a right triangle draw a line segment on a piece of paper.


2.Still using the right triangle find half of the line segment that you made and make a little mark.


3.Using the right angle of your triangle make another line segment intersecting your original one.


4.Now you can make your ninety degree mark for your right angle.


The third way to make a bisect perpendicular line.


I just found a video to help you with perpendicular lines using a compass.

Just click on this link.

http://www.youtube.com/watch?v=QT28JgIep48

I hope you found my scribe post helpful!









How to draw parallel lines
  1. Fold paper
  2. Use ruler and a right triangle







How to draw a perpendicular lines

  1. Fild paper


  2. Use protractor protractor ----------->











Tuesday, November 17, 2009

How to draw parallel and perpendicular lines

How to draw parallel lines
  1. Fold Paper
  2. use a ruler











How to draw perpendicular lines

  1. Fold paper
  2. Use protractor

















http://www.aaamath.com/



















For homework remember to do page 86-88 number 1-16 and do all numbers.

Monday, November 9, 2009

test

Due to the Remembrance day service we will only have a test on Thursday. Be sure to study each night this week.

Friday, November 6, 2009

Term Test

A reminder that we have a quiz on Tuesday, covering adding, subtracting, multiplying, and dividing decimals. Order of operations will be covered on the test as well.

Lastly, we have a Term Test on Thursday it will cover the entire term's worth of work. Be sure to start studying now, do not wait until the last minute!

Thursday, November 5, 2009

November 5th Mathematics

Find the amount each shape weights.



Today's number of the day is :

8497.365

1. Half of the number of the day is : 4248.6825


2. Write the number of the day in expanded form : 8000+400+90+7+0.3+0.06+0.005


3. Write the number of the in written form : Eight thousand four hundred ninty seven and three hundred sixty five thousandths


4. Round the number of the day to the nearest 100 : 8500


5. What digit is in the tenths place : 3


6. The number of the day doubled is : 16994.73


7. 123.45 more than the number is : 8620.815


8. 987.65 less than the number is : 7509.715


10. Cube the digit in the ones place : 343


11. Square the digit in the hundreds place : 16


12. Divide the number by 3.55 and round to the nearest hundreth : 2393.62


13. The product of all the digits in the number of the day is : 181440


For math practice, go to http://www.aaamath.com/grade7.htm


Textbook stuff is homework for the weekend. Do pages 71-73 questions 4-24. Remember to do the even ones only. Due Monday, November 9th 2009.

Wednesday, November 4, 2009

Number of the Day

Today's number of the day is:2691.348

1. Half of the number of the day is: 1345.674

2. Write the number of the day in expanded form:2000+600+90+1+0.3+0.04+0.008

3.Write the number of the day in written form:Two thousand six hundred ninety one and three hundred forty eight thousandths

4. Round the number of the day to the nearest 100:2700

5. What digit is in the tenths place:3

6. The number of the day doubled is:5382.696

7. 123.45 more than the number of the day is:2814.798

8. 987.65 less than the number of the day is:1703.698

10. Cube the digit in the ones place:1

11. Square the digits in the hundreds place:36

12. Divide the number by3.55 and round to the nearest hundredth:758.13

13. The product of all digits in the number of the day is:10,368




Don't forget to study for the quiz tomorrow!

Tuesday, November 3, 2009

Home Work

A) 2+3x4=14 B)10-6 ÷ 2=7
2+12= 14 10-3=7
14=14 7=7

C)(2+3)x4=20 D)(10-6)
÷ 2=2
5x4=20 4÷2=2
20=20 2=2

E)8÷22=2 F)4x3÷2+5=11
8÷4=2 6+5=11
2=2 11=11

5x15+33-(156÷2)=6
5x15=75
3x3=9
78-84=6
156÷2=6




Monday, November 2, 2009

Order Of Operations

There are 4 operations:


1st. Brackets
2nd. Exponents
3rd. Divide or Multiply in order from left to right.
4th. Addition or Subtraction in order from left to right.

(6.4+120)x1.25=156.4

What sign goes where? +, /
5.2 / 4 + 2.1= 3.4
1.3+2.1=3.4

Annie has been asked to calculate 1.7+6+2. She claims the answer is 3.85. Do you agree? Explain why or why not.

I don't agree because the answer i got was 9.7. I think she added it wrong. i calculated 1.7+6 and it equaled 7.7 then i added 2 and i got 9.7