Ninth graders learn function notation — the powerful f(x) symbol — understanding that it names a function and shows the input, and learning to evaluate f(x) by substituting a value for x.
Students will be able to…
You’ll see f(x) everywhere in algebra. It looks mysterious — but it just names a function and shows its input. What does f(x) really mean, and how do you use it?
Project this and change the function and the input x. Watch f(x) evaluate — substitute the input, get the output!
Tap any phase to open the teacher moves and student actions.
f(x) is everywhere in algebra — what does it actually mean?
Teacher models.
Class uses the Function Machine.
Students evaluate.
One evaluation.
Aligned to the Common Core State Standards for Mathematics (High School Algebra).
Use function notation and evaluate functions for inputs in their domains.
Understand a function as a rule assigning each input one output.
Relate the domain of a function to its graph.
Interpret key features of functions.
Preview the three formative checks. Tap “Sample answer” to see what mastery looks like — hide them before you print for students.
Have students work in reverse — given f(x) = 3x − 2 and an output of 10, find the input x. A printable function-notation sheet is in the Math library.
Tap a card to flip it, then rate whether you knew it. Built from this lesson’s vocabulary.
A quick self-check with instant feedback, drawn from this lesson’s key terms.
A print-and-go review sheet with a built-in answer key. Tap “Show answer key” to reveal answers, or print the clean version for students.