Appetizers and Lessons for Mathematics and Reason (www.whyslopes.com)
||Définition d'une variable || Algèbre || Arithmetique || Logique ||La raison basée sur les règles et modelés||

Online Volumes
1,  Elements of Reason.
1A. Pattern Based Reason 
1B. Math Curriculum Notes
2. Three Skills for Algebra
3. Why Slopes & More Math

 (Optional Book Orders)
More Site Areas 
1. Help Your Child or Teen Learn 
2. Solving Linear Equations
3. Fractions Ratios Rates Proportions & Units
4. Euclidean Geometry
5. Analytic Geometry/Functions 
6. Number Theory
7. More Calculus
More Site Areas 
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9. Qc Maths  Education  
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15. Algebra, Odds & Ends, Etc
More Site Areas 
16. Math Education Essays
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to work online with others.

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YOU are better than YOU think. Show yourself  how:  

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Read  logic chapters 1 to 5  in online volume Three Skills for Algebra  for greater skills & confidence in  work 
and study

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 Logic chapters 1 to 5  re- appear not in sequence, as is or longer,  in  Volume 1A,  Pattern Based Reason, Bon Appetite.

Logic Mastery
 Amazing, Amusing, Amorous,  Delicious, Delightful, Edifying, Strengthening Elixir. 
It eases work & learning difficulties Makes the hard easier. Opens eyes. Leads to greater precision.
in reading and
writing

Logic mastery makes the hard, easier. Logic mastery  leads to better, stronger and richer comprehension.  Logic mastery  improves reading and writing.  Logic mastery ease learning difficulties.  Logic mastery gives a headstart.  In sum, logic mastery  will develops critical thinking, improve reading and writing, and give a firmer base for work and studies at many levels. Good luck.


After logic  (a) continue reading Three Skills for Algebra, chapters 8 to 14  and do so alongside site area on solving liinear Equations ; or (b) see this calculus starter lesson and Volume 3, Why Slopes  & More Math, chapters 2 to 6;

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Caution: Site advice is approximately correct, for some circumstances, not all. That leaves room for thought

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What may be learnt and when depends on how skills and concepts are developed. Making the hard easier and clearer will allow earlier & richer development of skills and concepts.


Try the Twiddla Whiteboard. In principle, it  allows to people to draw and chat together online on a copy of this webpage or a clean sheet. The chat may be via text or audio.  Visit www.twiddla.com to set up whiteboards to work with the webpage of your choice.

For online automated help in senior high school maths & calculus, visit  quickmath.com  For Automatic Calculus and Algebra Help with derivatives, integrals, graphs, linear equations, matrix algebra, visit calc101.com  With  overlap, each site quickmath & calc101offers a different range of services, some free, some not, all based on webmathematica. Good luck.

Example 4:  Solve 3x - 4 =-11 (animated presentation)

Observe Error Recovery & Advice in Solution

Example 5:  Solve x + 12 = 10x - 30 

Operation Equation
given x + 12 = 10x - 30 
add -x to both sides 12 = 9x - 30 
add 30 to both sides 42 = 9x
Switch sides 9x = 42
Divide both sides by 9
(or multiply by 1/3)
x =  42
9
=

3*14
3*3

= 14
3
= 4 2
3

Note:

  1. We could have added  -x + 30 to both sides in one step, not two.
  2. We switched sides for cosmetic reasons.  That is we prefer to write b =15 in place of 15 = b.
  3. The switch would not have been needed if we had started with the equation 10x - 30 = x + 12  instead of x + 12 = 10x - 30. If x is a solution of one, it is also a solution of the other.  This switch would have put the bigger coefficient on the left hand side and result in  9x = 42. 
Operation Equation
given x + 12 = 10x - 30.
switch sides to get bigger
coefficient for x on left.
10x - 30 = x + 12
add -x to both sides 9x - 30 = 12 
add 30 to both sides 9x = 42 
Divide both sides by 9
(or multiply by 1/3)
x =  42
9
=

3*14
3*3

= 14
3
= 4 2
3

You see the solution does not change. 

Check: For 

x =  4 2
3

we have

LHS  =  x+ 12

 RHS = 10x-30

4 2
3
+ 12
= 10 (4 2
3
-30
= 16 2
3
= 40 + 20
3
- 30
= 10 + 6 2
3
= 16 2
3

Observe the left hand side (LHS) has the same value as the right hand side (RHS).  So the value 

x =  4 2
3

works.

Example 6:  Solve -3x + 4 = 10

 

 

Example 7:  Solve 6x + 4 = 4x + 14

Solution Steps:

Operation Equation
given 6x + 4 = 4x + 14.
add -4x to both sides 2x + 4 = 14
add -4 to both sides 2x=10
multiply both sides by ½ x = 5

We could have added -4x + -4 to both sides in one step instead of two.

Check: For x =5

Left Hand Side  = 6 x + 4
= 6*5+4
= 30+4
= 34
Right Hand Side = 4x + 14
= 4*5+14
= 20 +14
= 34

So for x =5, the Left Hand Side and Right Hand Side have the same value. 

 

 

www.whyslopes.com
Solving Linear Equations 

|(Feb 14, 2005)

a secondary I to V reference  for  solving linear equations and for  recognizing word problems in essentially one variable whether you like it or not, skill in arithmetic with fractions is a must for algebra. .

Area Entrance
Proper Use of Equal Sign
A. Letters and Lengths
B.. Solving Linear Eq'ns.
C. Solving Linear Eq'ns
D.Almost One
E: 2D Systems - Sub Method.
E:  Continued
E: Still More
F. Larger Systems


Area Entrance
(i) x + 20 = 29
(ii) 2x + 5 = 20
(iii) 3x + 10 = 32
(iv) 5a + 16 = 3a+ 24
(v)  (½)x + 8 = 24½
(vI)  (¾)a + 16 = (¼)a+ 24
(vii) (¾)q + 17 = 32
(viii) 13 =[2/3]x +7 twice
(x) Animated Examples
(i) Integral Coefficients (A)
(ii) Integral Coefficients (B)
(iii) Fractional Coefficients
(iv) With parameters



 


Arithmetic Videos

Decimal Addition Methods
Decimal Subtraction Methods
Decimal Multiplication Methods
Decimal Division Methods


Fractions
Primes
Greatest Common Divisors

Least Common Multiples

Square Root Simplification

Site books and further webpages on learning and teaching mathematics and pattern based reason may develop critical thinking, improve reading and writing, and give a base for learning or teaching high school and college mathematics.

Great_Expectations: If you can learn to follow a multi-step methods in any subject precisely, you can do so in other subjects, as well.

Good news: Site pages  identify what you need to study.

Bad news: Site pages do not explain everything  

Worse news: Learning takes time, yours

Lesson Plans and Ideas for Teachers & Tutors:

Secondary I - fractions & allied concepts (decimals, percentages)

Secondary II - Algebra  (arithmetic versus algebraic methods, backward use of formulas and proportionality equations)

Secondary IV - Functions to Trig & Statistics

Calculus Intro 

Algebra Lesson Notes - All levels


 

 



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