Rules for Integers - In Algebra you are always adding - either you are adding like signs or unlike signs.
Addition
Like signs add the value and keep the sign
Different signs subtract values and keep the sign of the greater number
*Please note that when we use the term value, we are referring to absolute value of number.
Subtraction(adding unlike signs)
To subtract an integer add its opposite or additive inverse than use the rules for addition.
(K - keep the sign of the first term)
(C - change the sign from subtraction to addition)
(F - flip the sign of the next term-use the opposite sign)
Multiplication and Division
Of course, positive x positive = positive
positive/positive = positive
When solving algebraic equations and your answer results in a negative variable, the answer is not in simplest form. Just reverse the signs on each side of the equation.
-x = 2
x = -2
This is not magic - you are dividing both sides of the equation by -1.
REMEMBER - just because we do not write the coefficient 1 before a variable does not mean that the 1 is not there.
-x can be written -1x
-1x = 2
x = - 2
Addition
Like signs add the value and keep the sign
Different signs subtract values and keep the sign of the greater number
*Please note that when we use the term value, we are referring to absolute value of number.
Subtraction(adding unlike signs)
To subtract an integer add its opposite or additive inverse than use the rules for addition.
(K - keep the sign of the first term)
(C - change the sign from subtraction to addition)
(F - flip the sign of the next term-use the opposite sign)
Multiplication and Division
+
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+
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Of course, positive x positive = positive
positive/positive = positive
When solving algebraic equations and your answer results in a negative variable, the answer is not in simplest form. Just reverse the signs on each side of the equation.
-x = 2
x = -2
This is not magic - you are dividing both sides of the equation by -1.
REMEMBER - just because we do not write the coefficient 1 before a variable does not mean that the 1 is not there.
-x can be written -1x
-1x = 2
x = - 2
