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On the Road

Four vehicles travelled on a road. What can you deduce from the times that they met?

Enclosing Squares

Can you find sets of sloping lines that enclose a square?


Change one equation in this pair of simultaneous equations very slightly and there is a big change in the solution. Why?

Painting Between the Lines

Age 11 to 16
Challenge Level
You may find it useful to explore the equations of straight lines using the interactivity in Parallel Lines.