Beginner Algebraic Expressions

Notes

What is an algebraic expression? An expression that contains one or more variables.

To evaluate: Substitute the variables with their given values, then follow the Order of Operations.

Steps

1. find the missing values to fill in the variables
2. re-write the equation by plugging the missing values in
3. solve following the order of operations

Variables

Variables are letters that represent an unknown value.

Example: 7==x== + 8

How am I supposed to find the variables’ values?

The question will usually give you the value of the variable that is included. If not, the variable’s value is its letter.

Examples: 7x + 8 ==(x = 3)==

Example Problem

7x - 2y (if x = 4 and y = 3)

7 x 4 = 28

2 x 3 = 21

28 - 21 = 9