### Why do this problem?

This
problem offers students a chance to consolidate their
understanding of coordinates whilst challenging them to think
strategically.

### Possible approach

Demonstrate the problem to the class, either using the
interactivity, or with a grid drawn on the board.

Give students about 10 minutes to work on the problem, either at
computers, or on paper in pairs - taking it in turns to choose
where the giraffe is and give the distances. Pairs can keep score
of the number of guesses each student required to find the giraffe
- the one with the lowest total wins.

Ask the class to share efficient strategies/useful ideas. Encourage
the students to consider all the points that satisfy each
condition, and to look at the shape of this locus. Re-emphasise
that the problem is to develop a strategy to find the giraffe with
the minimum number of guesses.

Return to the computers/pairs to work on the suggested strategies.
Provide squared paper for rough jottings.

If students are familiar with coordinates in 4 quadrants, the game
can be an excellent context for practising these - working on paper
with suitable grids.

### Key questions

Which points satisfy the conditions given so far?

How can you narrow down the possibilities?

### Possible extension

Play the game on a grid with axes from -9 to 9. Restrict the
guessing to the central square -5 to 5, but insist that the giraffe
is lost outside this central square. Students are allowed one
'final answer' guess outside the square to locate the
giraffe.

### Possible support

Encourage students to draw the situtation on squared paper, and
colour code points that are possible/impossible; looking at the
result of each new piece of information.