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Point C ii

In this movie we again move C along a line parallel to AB. We show the same four postions of C but now also highlight the resulting base and height each time. As can be seen, except for C1 they have the values 3 and 4 (or 4 and 3), so it easy to see that the area of the triangle is 6 unit squares.

For C1 we get a right-angled triangle but the lengths of the base and height are less straightforward (involving root 2). We look more closely at this on the next page.