Objective:
To add and subtract numbers with and without the number line.Vocabulary
- Real Numbers - points that can be plotted on a number line.
- Integers - positive and negative whole numbers and zero.
- Opposites - numbers found the same distance from, but on opposite sides of the origin.
- The opposite of a is − a.
- The opposite of −a is a.
- The opposite of 0 is 0.
- Absolute Value - the distance between the origin and the point representing a real number. Distance is always positive. What ever comes out of the absolute value symbol will ALWAYS be positive.
Notes:
Properties of Addition
Addition/Subtraction Rules
- If there are more than two numbers, add all of the positives together to get one positive term and add all of the negatives together to get one negative term then ...
- When there are only two numbers ...
- If the signs are the same, add and keep the sign.
- If the signs are different, subtract and keep the sign of the larger number.
Use this as a guide when two signs are next to each other (touching):
Examples:
