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Angles
In IGCSE Mathematics, you should know that:
- Sum of the interior angles: 180(n-2)
- The exterior angles in a polygon add up to 360 degrees
Corresponding angles
![broken image](http://custom-images.strikinglycdn.com/res/hrscywv4p/image/upload/c_limit,fl_lossy,h_9000,w_1200,f_auto,q_auto/4936730/319441_574853.jpeg)
Alternate angles
![broken image](http://custom-images.strikinglycdn.com/res/hrscywv4p/image/upload/c_limit,fl_lossy,h_9000,w_1200,f_auto,q_60/4936730/950564_661054.gif)
Interior angles
![broken image](http://custom-images.strikinglycdn.com/res/hrscywv4p/image/upload/c_limit,fl_lossy,h_9000,w_1200,f_auto,q_auto/4936730/116206_160797.png)
Trigonometry for Right-angled Triangles:
![broken image](http://custom-images.strikinglycdn.com/res/hrscywv4p/image/upload/c_limit,fl_lossy,h_9000,w_1200,f_auto,q_auto/4936730/650725_838518.png)
SOH CAH TOA
In IGCSE Mathematics:
SOH stands for sine=opposite/hypotenuse
CAH stands for cosine=adjacent/hypotenuse
TOA stands for tangent=opposite/adjacent
Label Sides
Side opposite to unknown angle should be labeled as opposite
The side next to unidentified angle should be labeled as adjacent
Longest side of triangle should be labeled as hypotenuse
Sine, cosine, tangent - Side lengths of a triangle
Sine-1, cosine-1, tangent-1 - Angles of a triangle
End of this topic!
![broken image](http://custom-images.strikinglycdn.com/res/hrscywv4p/image/upload/c_limit,fl_lossy,h_9000,w_1200,f_auto,q_60/4936730/265434_255167.gif)
Drafted by Gina (Mathematics)