Solving one-step equations

1. Using inspection, mental math

Eg. a + 4 = 12
8 + 4 = 12
12 = 12

Ask yourself what something + 4 = 12 or 12 - something = 4

Try these:

14 = k + 5
14 = 9 + 5

t - 3 = 11
14 - 3 = 11

10 - y = 8
10 - 2 = 8


2. Model (make a picture) and solve

Eg.


Bill rides 4 km to the bridge then rides to work. In total he rides 11 km. How far from the bridge to work?



4 + y = 11

4 + 7 = 11






3. Apply the opposite operation


Eg. c + 22 = 56
- 22 = -22
c = 34

Check- c + 22= 56
34 + 22 = 56
56 = 56



1st step - Isolate the variable (get the letter by itself)

2nd step - Apply the opposite operation

3rd step - Check your answer. Substitute the answer for the letter of the original equation



Opposite operation - An operation that "undoes" another operation
* subtraction and addition are opposites
* division and multiplication are opposites

Solve by applying the opposite operating - Check your answer:


1. n + 7 = 26
- 7 = -7
n = 19

Check - n + 7 = 26
19 +7 = 26
26 = 26

2. d - 3 = -5
+3 = +3
d = -2



Check - d - 3 = -5
(-2) - 3 = -5
-5 = -5








Page 398-401 # 1-22 is HOMEWORK!
http://www.mytextbook.ca/

Math Playground

Try some of these games, during your long weekend.

http://www.mathplayground.com/

Soliving Equations

Solving Equations:

Equation - a mathematical statement with two expressions that have the same value.




2b + 1 is EQUAL to 5

one way is to for you to use a scale.


[ps , i am sorry I can not do a cup so I am going to draw a square instead]
1c + 4 = 5



1c + 4 = 5






2c(cups) + 3 = 5



Writing expressions - the expression can be writen using a single constant,a single variable or a combination of operations with constants , variables, or numeral co efficent

2 - numerical co efficient
y - variable
7 - constant

Write the following Equation




c + 3 = 7


expression - 3 5
variable - c
numerical coefficiant - 3
constant is - 5




equation - 4 + 10
variable - c
numerical coefficiant -2
constant -4, and 10.

Show using cups + counters
four times a number minus five equals
write an expression or a eqution
I.D variables, numerical coeficents, constands

Websites :
http://www.studygs.net/equations.htm
http://www.sosmath.com/algebra/solve/solve0/solve0.html (might help with future reference.)

I am sorry but I couldn't find a video because they were too advanced

Integers

Using a number line to add integers.

A vertical Number line.

Just in case:
Zero pair - A pair of integer chips with one chip representing +1 and 1 chip representing.
Opposite integers - Two integers with the same numeral but different signs.

(+2) + (+3) = 5

(-4) + (-2) = -6

(+3) + (-2) = 1

Positive Numbers move right. Negative numbers move left.

A number line can be vertical also.

Here's a website to help you:
http://www.mathleague.com/help/integers/integers.htm

Here's also a video if this helps.
http://www.youtube.com/v/27CJH60xwuA&hl=en_US&fs=1&color1=0x402061&color2=0x9461ca

Page 319 - 322 is homework! :]

April 14 2010 Integers

Zero Pair

-a pair of integer chips with one chip reperesenting +1 and -1.

eg. +1 -1

The pair represent 0 because

(+1) + (-1) = 0

Opposite Integers

-two integers with the same numeral (number) but different signs. (+ -)

eg. + + - -

+2 -2

You can use these symbols to help add positive and negative integers.

eg. + + + + + - - - + - zero

+ - zero

+ - zero

+ +1

+ +1

5 + (-3) =2

Show using chips

(+2) + (+3) (-1) + (-5) (+4) + (-2) (+3) + (-6)

++ +++ = ++2 - - - - - - - - -2 ++++ - - + - 0 +++ - - - - - - + - 0

++2 - -1 + - 0 + - 0

+ 1 - -1 + 1 + - 0

- -1 + 1 - -1

- -1 - -1

- -1

Here's a good video about adding and integers

Here's a link to a good site

http://www.mathsisfun.com/positive-negative-integers.html

Sorry about having no pictures something was wrong with saving it.

Remember!!!

Pg.313 to 315 is homework!!!

Comment and suggest if you see any mistakes. Thanks

Integers

Integers-positive and negative whole numbers and zero
*eg. 2, -6, 91, +103, -10000

..not integers. 3/4, +1/2 , 4/5, 0.1. -0.7, 91.3, 95%, -60%

Integers can be shown on a number line or using integer chips..

Create Circle Graphs

1. Construct(make, build) a circle
Use a string, compass or trace a circle.
2. Create the Central Angles
- central angle- is an angle formed by 2 radii
- the vertex of the angle is at the centre of the circle

















25% like strawberry
25% like vanilla
50% like chocolate

















Make a graph for the following info. 3 kids use the computer 1-3 days per week.
9 kids use the computer 0 days per week. 18 kids use the computer 4 or more days per week.

Step 1. Find out how many in total.
3+9+18= 30

Step 2. Convert to %
3 = 1 = 10 10% 1-3 days
30 10 100

9 = 3 = 30 30% 0 days
30 10 100

18 = 6 = 60 60% 4 or more days
30 10 100








%|degrees
100|360
50 | 180
25 | 90
10 | 36


Convert % to degrees.
10% of 360= 36 degrees
use a protractor to measure the central angle

30% of 360= 108 degrees
60% of 360= 216 degrees


Homework
Pages 296-297
Questions 4-13