What are the key features of a quadratic and what information do you need to be able to identify these for a particular example?

This problem is designed to be tackled in a team of four, working as two pairs. One of the pairs is trying to identify the quadratic on a randomly chosen card from this set of cards.

Instructions

  • To begin, place all of the cards on the table and spend a couple of minutes familiarising yourselves with the types of images and equations that might be chosen.

  • Next, one pair takes control of the cards, moving them out of sight from the other pair. They select a card at random. The other pair can now ask up to 8 “yes/no” questions to determine the hidden quadratic. It is important that each pair confers and agrees before asking or answering each question.

  • You are permitted a maximum of two guesses at the hidden function, and each guess counts as one of your 8 questions.

Some things to consider

  • Did you guess the quadratic correctly? If not, what additional information did you need?

  • Did you make the most of the information you were given? Could you have avoided asking any of your questions?

  • Were your questions clear? Did the other pair understand what you meant? Could you have used mathematical language to improve this?

  • Would you ask the same questions next time?

Plot of y equal x squared.
Plot of y equal minus x squared.
Plot of y equal x squared + 2.
Plot of y equal minus bracket x + 2 close bracket squared minus 2.
Plot of y equal minus bracket x minus 2 close bracket squared minus 2.
Plot of y equal minus bracket x + 2 close bracket squared.
Plot of y equal minus bracket x minus 2 close bracket squared.
Plot of y equal 2 minus bracket x minus 2 close bracket squared.
Plot of y equal 2 minus bracket x + 2 close bracket squared.
Plot of y equal bracket x + 2 close bracket squared minus 2.
Plot of y equal bracket x minus 2 close bracket squared minus 2.
Plot of y equal bracket x minus 2 close bracket squared + 2.
Plot of y equal bracket x + 2 close bracket squared + 2.
Plot of y equal bracket x minus 2 close bracket squared.
Plot of y equal bracket x + 2 close bracket squared.
Plot of y equal x squared minus 2.
Plot of y equal 2 minus x squared.
Plot of y equal minus 2 minus x squared.