Thursday, 29 December 2011

Simplifying Expressions - Removing Brackets

Algebraic expressions can contain brackets. In order to simplify these kind of expressions, you may need to remove the brackets.

The video lesson below shows you the basics that you need to know when removing brackets.




Example: Remove the brackets and simplify the following expression .

Step 1:  First, let's remove the brackets in -(5x -3).



                    

Step 2: Multiply -1 and 5x together.You will get -5x. Note that "-" is the same as "-1").                                                        



Step 3: Now, multiply -1 and -3 together. You will get +3.




Step 4: Put back -5x +3 into the expression. Next, we remove the brackets in   2(4x -2).


Step 5: Now, multiply 2 and 4x together. You will get +8x.




Step 6: Now, multiply 2 and -2 together. You will get -4.    




Step 7:  Put back 8x -4 into the expression. The expression now becomes:             
Notice that this expression has like terms. Therefore, let's arrange the like terms together. The expression now becomes:

Step 8: Now, simplify the expression by adding +3 and -4. You will get -1.


Step 9: Now, simplify the expression by adding +8x and -5x. You will get 3x.


Step 10: The expression becomes 3x-1. There is no more like terms, therefore this is the simplest expression.