ABC is an equilateral triangle.
Determine the size of angle ?
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ABC is an equilateral triangle.
Determine the size of angle ?
In order to solve this exercise, we need to be aware of two important laws-
1: In an equilateral triangle, all angles are equal.
2: The sum of angles in a triangle is 180.
Let's begin by defining the angle size as X.
We know that all angles are equal, and together they equal 180 degrees, therefore:
3X=180
Divide by 3
X=60
Hence the angle size is 60 degrees!
60°
Find the measure of the angle \( \alpha \)
Equilateral triangles have all 3 sides equal and all 3 angles equal to 60°. Isosceles triangles have only 2 equal sides and 2 equal angles. Don't mix them up!
Since all angles are equal, we can call each angle x. The triangle angle sum gives us: , so , which means .
No! Once you know a triangle is equilateral, you automatically know each angle is 60°. The diagram just helps you visualize - the math property is what matters.
It doesn't matter how the triangle is oriented or drawn! If all three sides are equal, then it's equilateral and each angle is always 60°, regardless of position.
The angle sum method works for any triangle: the angles always add to 180°. But only equilateral triangles have the special property that all three angles are equal to 60°.
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