Sine Rule

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The first sheet of this interactive excel file provides students with calculations to confirm that a/sinA=b/sinB etc. The next two sheets give sufficient information to allow students to calculate all the unknown lengths and angles of a given triangle. Answers can be revealed and new questions generated. The ambiguous case is illustrated and dealt with on a separate interactive sheet.

The next sheet requires students to be able to calculate areas of triangles. Further practice is given in a sheet showing a table of various pieces of information about lengths and angles of triangles so that other dimensions and the area can be calculated.

The final interactive sheet uses the formula for the area of a triangle and the Cosine Rule in a proof of Hero's Formula.

There are a further five sheets of questions which may be suitable for use in the classroom.


This program was designed by be viewed on a screen with a resolution of 1024 x 768. Users may have to adjust the resolution of their screen for the pages to display as was originally intended. The program uses macros which need to be enabled on users' machines.

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