Reversing+Operations

__**Changing Addition to Subtraction:**__
by: Evan and Mr. Rochester

In order to change Addition problems to subtraction problems you must change the addition sign to a subtraction sign and change the sign of the second number.


 * Examples:**
 * 1) 5+3=8 can be rewritten as 5 - (-3)=8 (Otherwise known as, subtracting the negative)
 * 2) 5 + -3=2 can be rewritten as 5 - (+3)=2 (The -3 was changed to a 3)

__**Changing Subtraction to Addition:**__
by: Amira and Mr. Rochester

To change a subtraction problem to addition you must first know the rule for negative numbers. Rule 1: A negative plus a negative equals a negative. Rule 2: A positive plus a positive equals a positive. Rule: A positive plus a negative or a negative plus a positive depends on //absolute value// of the positive and negative number. If the //absolute value// of the negative number is bigger, then your answer will be negative.

Here's how to change subtraction problems to addition.

Step1:Change the subtraction sign to addition. Step 2: Change the sign of the number that you were going to subtract.

Example: 5 - 3 Step 1: 5 + 3 Step 2: 5 + -3

Thus we have, have 5 - 3=2 which can be rewritten as 5 + -3=2.

media type="custom" key="379253"

edited by Mr. Rochester

__**Changing Multiplication to Division**__
by: Ian

To change multiplication to division you have to change the multiplication sign to a division sign, then you'll need to make the second number a fraction by using it as the denominator and using 1 as the numerator. Example: Change 4•5 go a division problem.

They both equal the some amount. math 4 * 5 = 4\div\frac{1}{5}=20 math You can even use a calculator to check your results.
 * Step 1:** 4÷5
 * Step 2:** 4÷1/5
 * Solve:** 4÷1/5=20
 * Compare:** 4•5=20

edited by: Mr. Rochester

__**Changing Division to Multiplication:**__
by: Rumman


 * When dividing fractions and if you find multiplication easier you can change it in the following steps:
 * 1) Leave the first fraction or number as it is.
 * 2) Invert the divisor (Second Fraction) by finding the reciprocal or flip the fraction putting the numerator number into the denominator and the denominator number in to the numerator
 * 3) Last change the division sign to multiplication.


 * Example 1:**

math 2\div\frac{2}{5}=2*\frac{5}{2}=5 math


 * If the problem is just regular containing no fractions, then you:
 * 1) As we all know when there is a whole number and you want to change it to a fraction you use 1 as the denominator.
 * 2) After that you put 1 as the denominator for both parts.
 * 3) Then you follow the steps above and leave the first part as it is
 * 4) For the divisor find the reciprocal or flip the fraction which would make the 1 the numerator because you flipped it.

math 2\div5=\frac{2}{1}\div\frac{5}{1}=\frac{2}{1}*\frac{1}{5}=\frac{2}{5} math
 * Example 2:**

edited by: Mr. Rochester