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Algebra 1

What is a function?

Algebra 1What is a function?
Search for key terms or text.

In this activity, whenever you see 💬, stop and share your responses with your partner. If you have different responses, try to come to a consensus.

In the first activity, you may have noticed that all of the simulation screens share a three-part structure. These three parts can be described in a variety of ways, such as the ones listed in the image below.

Diagram showing green boxes labeled input original before entering a tube labeled function operation action, transforming into yellow arrows, and exiting as orange boxes labeled output new after.

1. Come up with your own names or labels for the three parts of a function.

2. Share your labels with your group. Write down any similarities. 💬

For 3 - 4, use the following instructions.

Use the simulation screen labeled “Patterns”. Note you can switch between simulation screens using the toolbar located below the function builder.

3. The blue “builder” in the middle of the screen is a function. Describe what a function is using the labels you've agreed on as a class. 💬

4. Suppose you build this function:

A blue pipe with flared ends contains a green arrow pointing right. Inside the arrow is a black gear and a purple curved arrow indicating clockwise rotation.
  1. a. Complete the following table, sketching what happens after going through the function.
    Input Output
    A digital illustration of two red cherries with green leaves attached to their stems on a white background. Two red cherries with green leaves and thin white stems on a white background.
    A solid black heart shape with a pointed bottom and two rounded arches at the top, centered on a white background.
    A gray square button with rounded corners featuring a large white check mark in the center, symbolizing approval or completion.
    A yellow smiling face emoji with black oval eyes and a simple, closed-mouth smile on a white background.
    A close-up illustration of a ladybug with a red, black-spotted shell, six legs, and two antennae, shown on a white background.
    A simple, bold black plus sign centered on a white background.
  2. b. Write a rule that describes what the function does. Compare with your group. 💬
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