Algebra 1a: Chapter 1, Lesson 1, page 4.
Symbols and Expressions
In algebra, we use symbols to stand for various numbers. One type of symbol is called a VARIABLE. An expression such as `396/v` and contains at least one variable is called an ALGEBRAIC EXPRESSION. We can replace a variable with a number, this is called SUBSTITUTING for the variable.
Sets of numbers:
- Natural: 1, 2, 3, 4, 5, …
- Whole: 0, 1, 2, 3, 4, 5, …
- Rational: numbers which include natural and whole numbers and can be expressed as a RATIO such as `1/1` or `2/3`
Parenthesis (, ) or [,] or {,} are called GROUPING SYMBOLS and we do things in them first.
PEMDAS, please excuse my dear aunt sally – order of operations. Just like in Language Arts, we have a convention of writing/reading from left to right, we have a convention in math.
We do things in the order of:
- parenthesis
- exponents
- multiplication/division (in order from left to right)
- addition/subtractions (also in order from left to right).
Here is a link to tonight’s homework on Chapter 1, Lesson 1. There are 2 solutions provided. Remember, you need to have Quicktime for either the PC or Mac installed on your computer!