How to Find the Area of a Triangle

A triangle is a three sided figure that has three angles.
For example:
A triangle is half of a parallelogram. So the formula to find the area of a triangle is (b-base x h-height) divided by 2 (to get the height of a triangle you make a parallel
line from the base to the tallest vertex).
For example the base of the triangle is 2 cm and the Height of the triangle is 4 cm

First you have to multiply the 2 by the 4 to get 8

Then you divide 8 by 2 to get the area which is 4 cm
Here is a site that can help

here is a video

Area and Homework

Area

• The number of square units contained (inside) in a two dimensional shape.
  

- this square has an area of 4 units

• Area is the surface space takes up

Area of square or rectangle
- Length * width = area

- L * W = area= 18 cm Area = L* W
Area = 6*3
= 18cm Squared

Parallelogram
- A 4 sided figure with opposite sides parallel and equal.

Lines are hashmarks that are equal













Arrows are parallel to each other



base
- A side of a two dimentional closed figure (shape) (b)

A base is any side of a closed figure.
















Height
- the perpendicular distance from the base to the opposite side.

(h)















Area of parallelogram formula

A=b*h

Base (b) is 5 cm and height (h) 3 cm. Plug these values into the formula.
A=b*h
A=5*3
A=15 cm squared
















Find the area of this parallelogram:
A=b*h
Area=2*8
A=16 cm squared



Find the area of this parallelogram:

















A=b*h
A=12*4
A=48 m squared

Homework:

Ishaka's Garden
















What is the shape of the garden?
What is the area of the garden?
Ishaka is going to plant flowers in his garden.
He is going to plant per square metre.
How many flowers does he need to buy?

2nd Homework:
















Find the area of this shape?


If you don't understand here is a website and a video to help you!

Angles

Angles

The space between two connecting lines.

Acute

An angle that is less than 90°.

Obtuse
An angle that is greater then 90° and less than 180°

Right
An angle that is exactly 90°
Straight
An angle that is exactly 180°

Angle Bisector
The line that divides an angle into equal parts.
(equal angles are marked with the same mark)
Their are 3 ways to make an angle bisector.

1.a) Fold Paper until the 2 lines on your angle meet.
b) Use a ruler to draw a line on a crease.

2.a)Use a compass to make an arc from the vertex that crosses both arms. Label them x and y
b)Make an arc from point x and point y. They must be equal in size.
c) Draw a line from point B to the between the meter section.
3.a)Use a protractor.
(angle)
b)Measure the < D E F.

^
|
140°

c)Divide your measurement by 2. 140÷2= 70°.

d)Make a mark at 70° using a protractor. Label it Q.


e)Join point Q with the vertex with a straight line.
1. Make a 68° angle. Then draw the angle bisector using 2 methods.
2.How could you divide an angle into 4 equal parts ?
You can find out the angle and then divide it by 4.
3.Has each angle been bisected? How do you know ?

No because A is cut in half and B isn't cut into equal parts.

4.What are 2 examples of angle bisectors in the real world?
Pizza and Pie.
Here's a good link that could help you make Angle Bisectors.

Bisect & Perpendicular Bisector

Bisect
Bi means two
Sect means to cut
Bisect means to cut in two

Perpendicular Bisector

A line that divides another line segments in half and has right angles to it.


1st way to make a Perpendicular Bisector:

Fold the paper, so point A is on point B. Draw a line in the crease that you made. Label it C,D. Where they intersect, label it P.


2nd way to make a Perpendicular Bisector:

You have to use a Right Triangle.

Step 1,
Draw a line segment on a piece of paper with a right triangle.

Step 2,
Use the right triangle to find the half mark of the line segment.

Step 3,
Draw another line segment on the half mark, intersecting with the original

Step 4,
Make sure that it is 90 degrees. (use a protractor to check)

3rd way to make a Perpendicular Bisector:

Use a Compass.

Step 1,
Make an arc from point A that is greater than half way.

Step 2,
Make an equal sized arc from point B.

Step 3,
Connect the arc intersection with a straight line.

how to draw parallel and perpendicular lines

how to draw parallel lines
1.fold paper
2.use a right triangle

how to draw perpendicular lines
1.fold paper
2.use a protractor

http://www.scribd.com/doc/19705098/How-to-Draw-Parallel-and-Perpendicular-Lines-II

Parallel and Pendicular lines

Parallel and Perpendicular lines

Geometry- Shapes and measurements.

Parallel- Describes two lines in the same plane that never cross, or intersect.
- They are marked using arrows.


Here is a picture of parallel lines:


Perpendicular- Describes lines that intersect at right angles. ( 90°)
- They are marked using a small square
Here's a picture of a right angle

Measure the difference from:

A to B
B to C
E to F
F to G
I to J
J to K
They all are 8.9 cm.

Here's a video about Perpendicular lines


Here's the link: http://www.youtube.com/watch?v=Lc3dPkoCOHc

Identify any parallel lines you can find.
AE // BF, EI // FJ, CG // BF, GK // JF, AI // CK


What d0 you notice about parallel lines? they always are the same distance apart no matter where you measure, as long as you measure a perpendicular line.


Identify any perpendicular line segments.


AE __ DF , FE __ AI , BF __ EG , CG __ FH

What do you notice about perpendicular line segments? they all meet at 90° angles.

FOR HOMEWORK!
#1. Are line segments AC and DF parallel?
#2. Are line segments DF and BE perpendicular?
#3. Are line segments AC and BE 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?

Test

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

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!

Number of the Day !

Number of the Day

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 + .3 + .04 + .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 is:

2814.798

8. 987.65 less than the number is:

1703.698

10. Cube the digit in the ones place:

1

11. Square the digit in the hundreds place:

36

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

758.12

13. The product of all the digits in the number of the day is: ( Sorry guys, I had trouble with this one )

108.000096

If anyone has any questions, feel free to comment asking what you want to know!

Also, if you don't understand what I did, or if I did something wrong, please comment saying what I did.

Thank you !!

DON'T FORGET THE HOMEWORK, STUDY FOR THE TEST. *

Practicing With BEDMAS ( Order of Operations )

Today during math, we used BEDMAS to answer these questions below.
If you don't know what BEDMAS means, make sure to check Kimberly's scribe post!

a)
2+3x4 =
2+12 =
14

b)
10-6÷2 =
10-3 =
7

c)
(2+3)x4 =
5x4 =
20


d)
(10-6)÷2 =
4÷2 =
2

e)
8÷2² =
8÷4 =
2

f)
4x3÷2+5 =
12÷2+5 =
6+5 =
11



g) Create a math equation including +, -, ÷, x, brackets and exponents. The answer must be 6 and you can't repeat any digits or use zero.

This is what I got:

Here's a video on BEDMAS :

Order of Operations

There are 4 operations.
-addition
-subtraction
-multiplication
-division

Addition and subtraction are brothers and multiplication and division are sisters.

B E D M A S stands for:

Brackets ( )
Exponents
Division
Multiplication
Addition
Subtraction

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+120x1.25=
6.4+150=
156.4

Change this equation so the answer is 158.

The way you change the equation so the answer becomes 158 is you have to put brackets around 6.4+120.
(6.4+120)x1.25=
126.4x1.25=
158

What sign goes where? +, division sign

5.2__4__2.1=3.4

Here's the answer.

5.2 divided by 4+2.1=

1.3+2.1=

3.4

2x3 divided by 6+(2-1)=

2x3 divided by 6+(2-1)=

2x3 divided by 6+1=

6 divided by 6+1=

1+1=

2

(0.75-0.5)x(4.2 divided by 0.6)+7.3-1.2=

(0.75-0.5)x(4.2 divided by 0.6)+7.3-1.2=

0.25x7+7.3-1.2=

1.75+7.3-1.2=

7.85

Here is a link for more about the Order of Operations.

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

1.7+6 divided by 2=

1.7+3=

4.7

I do not agree because when I simplified then calculated it, the answer I got was 4.7.