Lesson 1: Write Two-Step Equations

Property

Algebraic expressions may involve two or more operations. Some algebraic expressions involve more than one variable. To write an algebraic expression from a phrase, we must identify the unknown quantities, assign variables to represent them, and then translate the mathematical operations.

Examples

• A delivery service charges 8 dollars per package plus a 10 dollar flat fee. The total cost for $p$ packages is $8p + 10$.

• The total number of books read by Leo and Mia can be represented by $L + M$, where $L$ is the number of books Leo read and $M$ is the number Mia read.

Property

Step 1. Locate the 'equals' word(s). Translate to an equal sign.
Step 2. Translate the words to the left of the 'equals' word(s) into an algebraic expression.
Step 3. Translate the words to the right of the 'equals' word(s) into an algebraic expression.

Examples

• 'Five more than $x$ is equal to 26' translates to the equation $x + 5 = 26$. The words 'is equal to' become the $=$ sign.

• 'The difference of $5p$ and $4p$ is 23' translates to $5p - 4p = 23$. The word 'is' becomes the $=$ sign.