# Guided Activity Guided Activity
The goal of this activity is to match a polynomial function to an unknown function and learn a bit about polynomial functions along the way. In other words, your goal is to match the unknown function g(x) by changing the values of the coefficients a, b, and c in your polynomial function, f(x)=y.
• Let the red curve on the graph be the known polynomial function, f(x).
• Let the dark blue curve on the graph be the unknown polynomial function, g(x).
• The thin curves represent individual contributions to f(x). Namely, ax2, bx, and c.
• Record all your observations, results, and analysis as they may be worth marks.
• Good hunting!

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# Question

 What is the y-intercept for the unknown function? What is the value of y when x=0?

 -2.5

Example Data Table More Guided Activity
You have completed the first part of the activity.

Now you need to match the entire function f(x) to the unknown function.

• Which way is unknown function's minimum (or maximum) shifted from x=0?
• With c=0, can you make the red curve not cross the blue curve?
• Now look at how broad the unknown function is for a specific range of x. Can you match the curve?