According to the data,
Calculate the size
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According to the data,
Calculate the size
Since we are given an angle of 147, let's calculate the angle ACB which complements it to 180 degrees:
Now we have two angles in triangle ABC, and we can calculate angle BAC:
57
Indicates which angle is greater
An external angle is formed when you extend one side of a triangle beyond a vertex. It's the angle outside the triangle, and it always adds up to 180° with its adjacent interior angle.
Because 147° is outside the triangle! If you used it directly, your triangle's angles would add up to more than 180°, which is impossible. You must first find the interior angle.
Look at the diagram carefully! The interior angle is inside the triangle shape, while the exterior angle is in the space outside the triangle where a side has been extended.
Yes! Once you find the interior angle , you can use: Missing angle = 180° - 90° - 33°. Just remember the triangle angle sum!
The same method works! Find the interior angle from the external angle, then use the fact that all triangle angles sum to 180° regardless of the triangle type.
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