Find the size of angle .
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Find the size of angle .
Note that the sum of the angles in a triangle is equal to 180 degrees.
Therefore, we can use the formula:
Then we will substitute in the known data:
Finally, we will move the variable to the other side while maintaining the appropriate sign:
111.3
Is the straight line in the figure the height of the triangle?
This is a fundamental property of triangles in flat (Euclidean) geometry. It's like a mathematical law - no matter what type of triangle you have, the three interior angles will always sum to exactly 180°!
If you get a negative result, check your addition first. Make sure you added the known angles correctly. A triangle angle can never be negative!
Absolutely! Angles can be any positive decimal value. Just make sure your final answer, when added to the other two angles, equals exactly 180°.
Use the same precision as given in the problem. Here we have 27.7° (one decimal place), so your answer should also have one decimal place for consistency.
That would mean the third angle is 0°, which is impossible in a real triangle. Double-check your problem - there might be an error in the given values.
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