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7th Grade - Algebra

7th Grade lesson

5 - Algebra


Unknow x

Algebra means calculating with a number x that we do not know. We can replace 'x' with '?'. This number whose value we do not know is useful for solving a problem whose solution we do not know.

x is an Unknow.

We can add and subtract two or more 'x's but we cannot add an 'x' and a number :
literal calculation


Distributivity

There are two methods to calculate distribution :
distribution
distribution

In order to calculate literal calculation, we cannot calculate the brackets first. We therefore use the second method, that is what is called distributivity.

simplification by distribution
simplification by distribution
simplification by distribution
simplification by distribution
simplification by distribution
simplification by distribution

We have seen what distributivity is. Let us now have a look at double distributivity.

Double distributivity

It is the same thing just a little bit longer.

Mathematical calculation. With double distributivity, this calculation gives us :
simplification within a calculation

Whenever there are unknows, 'x' means the same thing :
simplifying an expression
simplifying an expression
simplifying an expression

Make an effort to understand the signs very well. It is important to train yourself very well to be able to do literal calculation. Practice and literal calculation will greatly help you for the other chapters and in the higher grades.


See also : algebra on fmaths.com



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7th Grade Algebra

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