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The lightning flash with arrowhead symbol, within an equilateral triangle is intended to alert the user to the presence of uninsulated dangerous voltage within the product’s enclosure that may be of sufficient magnitude to constitute a risk of electric shock to persons.
Notice ADE is an equilateral triangle, so ∠DAE = 60◦ .
The canonical Sierpinski triangle uses an equilateral triangle with a base parallel to the horizontal axis (first image).
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Definition 1 A triangular number is the number of dots in an equilateral triangle uniformly filled with dots.
This sequence is derived by starting with a single object, and adding rows of increasing numbers of such objects in the form of an equilateral triangle.
Problem 3 Show that if the points of the plane are colored black or white, then there exists an equilateral triangle whose vertices are colored by the same color.
“Our Women are Straight Lines…Our Soldiers and Lowest classes of Workmen are Triangles with two equal sides…Our Middle Class consists of Equilateral Triangles…Gentlemen are Squares or Pentagons…Next above these come the Nobility, beginning at Six-Sided Figures, and from thence rising in the number of their sides…when the number of the sides becomes so numerous that the figure cannot be distinguished from a circle, he is included in the Circular or Priestly order.” (1, pg.
Triangular equilateral nicking tools.