Trigonometry

SOH CAH TOA in action:

Being able to calculate sides or angles enables accurate building and measuring.

Similar Triangles - Ratio of sides:

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  • Similar Triangles
  • The blue triangle has sides 9, 12 and 15.
  • The purple triangle has sides 3, 4 and 5.
  • The triangles have the SAME angles.
  • The sides of the purple triangle multiplied by 3 give the sides of the blue triangle.
  • The scale factor from purple to blue is 3.
  • The RATIO of the sides is the SAME.
  • 9/12 = 3/4 = 0.75
  • 9/15 = 3/5 = 0.6
  • 12/15 = 4/5 = 0.8

Label Triangles:

SOH CAH TOA

Useful Resources:

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