You can put this solution on YOUR website! Rule 1:
Addition of two Numbers with the sign
The result is the of the numbers with the sign ( the sign of the two numbers ) .
When we add two numbers we get a number. Example : .
When we add two numbers we get a number. Example: .
Rule 2 :
Addition of two numbers with signs the is the between the numbers with the sign of the" " .
Example:
Rule 3 :
Multiplication and signs :
The basic rules for multiplication and signs are as follows
This can be expressed as follows that
(a) when we multiply two numbers with the same sign we get
( b) when we multiply two numbers with difference signs we get a
Example :
Rule 4 : Letters
Letters are often used in place of numbers , letters are often referred to as or .
Rules 1,2,3 above apply to all calculations with letters , we have to remember which applies to letters that is , in other words we can only add x's to x's and y's to y's etc .
Example
....Note also means times.
or
}
or
Rule 5 : Brackets
(a) A number immediately outside a bracket means that everything inside the bracket gets multiplied by that number
Ex.:
(b)Minus sign outside a bracket will change all the signs inside the brackets when the brackets are removed :
Ex.:
(c)Minus number outside a bracket does two things
(1) everything inside the bracket gets multiplied by the number and
(2) all the signs change
Brackets by brackets :
Multiply everything in the second bracket by everything in the first bracket and tidy it up .
Ex.:
