# Working with Algebra Lesson 2: Substitution

Australian curriculum number (ACMNA190, ACMNA191, ACMNA192)

## Lesson abstract

This resource contains a collection of tasks focussing on substitution. In Expressing Relationships, students determine a range of values that make a two-variable equation true. In What Can It Be?, students explore options that will make an incomplete identity true. In Temperature Conversion, students find values satisfying the relationship between temperatures expressed in degrees Fahrenheit and temperatures expressed in degrees Celsius.

## Mathematical purpose (for students)

Practise substitution in algebraic expressions.

## Mathematical purpose (for teachers)

These tasks develop fluency with substitution into algebraic expressions. They enable teachers to identify and address student misunderstandings about the use of algebraic notation. The tasks offer students opportunities to create and communicate a variety of solutions. Teachers can create tasks like this involving algebraic expressions of any desired complexity.