Finding a length: the unknown underneath
Mathematics · Grade 9 · about 40 minutes
When the unknown sits on the bottom of the fraction, it swaps places with the ratio.
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Other lessons in this sub-strand
- Naming the sides of a right-angled triangle
- Sine, cosine and tangent
- Tables and calculators
- Finding a length: the unknown on top
- Finding a length: the unknown underneath
- Finding an angle
- Trigonometry in real situations