C2.1 Identify and use symbols as variables in expressions and equations.
Activity 1: Determining and Using Symbols in a Relationship
- Read the following scenario to students:
A cabinetmaker wants to make chairs. He needs legs.
- Ask students to write an algebraic expression that represents the statement.
- Ask questions such as:
- What are the unknown quantities? How do you know?
- What is the constant quantity? What are the variable quantities? Justify your answer.
- What symbols can be used? What is the reason for this?
Activity 2: Determine and Use Symbols to Represent Unknown Quantities
- Present students with the following scenario:
The school's physical education teacher is organizing a volleyball tournament for students in Grades 4-6 . To do this, he needs to know how many students in each grade will be participating. He knows that there are 92 students in Grade 4 and 102 students in Grade 6 , for a total of 300 students. He has yet to determine the number of students in Grade 5.
- Ask students to write an equation that represents this situation.