Using the interactivity below, line up the yellow and green dots so the two lines are the same. Then use the yellow dot to translate the blue line up, down, left and right.

Full screen version

Investigate what happens to the equations of different lines when you translate them up or down.

Try to predict what will happen. Explain your findings.

Now investigate what happens to the equations of different lines when you translate them left or right.

Try to predict what will happen. Explain your findings.

Below are the equations of ten lines, and some translations. Each translation links a pair of parallel lines - can you match them up?

Can you find other combinations of vertical and horizontal translations that link each pair of parallel lines?