Grade 9 Math · Algebra
Lesson 2.4
Modelling Situations with Equations
Turn a written situation into an equation, then use the equation to answer a question.
Estimated time: 45 minutes
Lesson progress0%
Learning goals
- I can turn a word problem into an equation.
- I can use an equation to make a decision.
Step 1 of 2
Learn
The idea, explained clearly — with the words mathematicians use.
Name the quantities first
Before writing an equation, decide what each letter stands for. Clear labels make the rest of the work easier.
- Variable
- A letter that stands for a quantity that can change.
Curriculum connection
These are the words your teacher and the Ontario curriculum use. Learn them here and use them when you explain your thinking.
- Curriculum languageMathematical model
- What this meansA mathematical model is an equation or graph that stands in for a real situation so you can reason about it.
Step 2 of 2
Mastery Check
Show what you can do now that you could not do at the start.
You have finished this lesson
- I can turn a word problem into an equation.
- I can use an equation to make a decision.
A unit check is waiting at the end of Algebra.