Step 8 Objective
Present a concise reasoned argument, using symbols, diagrams, graphs and related explanatory texts.
- Examples of what pupils should
know and be able to do - Probing questions
- What if pupils find
this a barrier?
What if pupils find this a barrier?
Line Crossings
- Draw three straight lines (line segments) so that some cross over each other.
- How many crossings are there?
- Try different arrangements of the lines. What is the maximum number of possible crossings?
- Try using more lines.
- Is there a rule for the maximum for any number of lines? If so, write it down.
Use the problem Line Crossings.
- Look at the table of results and explain the patterns you see.
- Can you predict what the next number in the table (pattern) would be?
- Are you sure? (Check by drawing this.)
