Introduction of Algebra

 What is Algebra? This posting will answer your question about Algebra.

Try to Solve this puzzle.

Can you guest What is the missing number?

−

5

=

10

Correct, the answer is 15, Why? Because 15 − 5 = 10. So Easy right?

In Algebra,  we use a letter to represented the missing number. (you can use any letter from a until z). For example, we will use letter m. So we write:

m

−

5

=

10

So simple, right? The letter (in this case an m) just means "unknown number", and is often called the variable.

And when we get the answer, we can write as :

m

=

15

See also : Facts of interseting Numbers

How to Solve

Algebra is jas simple as a puzzle right? You can start with  a question like :                "m − 5 = 10" and think the unknown mumber. Oh... m is 15

But instead of saying "obviously m = 15", to solve it, use this steps:

1. Find out the unkown numbers. Example you want to get "m = ..."
2. Remove it by doing the opposite (adding is the opposite of subtracting)
3. Do that to both sides

Here is the way:

We want
to remove
the "−5"

m - 5 = 10

 

To remove it, do
the opposite, in
this case add 5 both sides

m - 5 + 5 = 10 + 5

 

Geting The Answer  (Done)

m = 15

 

Why did we add 5 to both sides? To "keep the balance". 

See this another example : Find the 'unknown numbers for x - 2 = 4

x - 2 = 4

See the picture, we want to make it ballance

In Balance

 

Add 2 to Left Side

Out of Balance!

 

Add 2 to Right Side Also

In Balance Again

Please Remember this :

To keep the balance, what we do to one side of the "=" we should also do to the other side!

Try This for your exercise : 

Solve this one:

x

+

7

=

19

See also : What is Equation?

(Resource)