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DFN: we call a triangle equilateral if all sides of the triangle are the same length
DFN:we call two triangles similar if corresponding angles are equal, and corresponding sides are proportional.
First show that all corresponding sides are proportional:
Consider a equilateral triangle with side lengths 1, all other equal lateral triangles sides can be expressed as S*(1), where S is some scalar. Hence all equilateral triangles sides are proportional to each other.
Next, show that all corresponding angles are equal:
The angle between two sides of a triangle is related to the length of the sides. These relationships are called sin, cos, and tan. Knowing that the cos(x), where x is one of the angles in the triangle, is the adjacent divided by the hypotenuse we see that cos(x)=(1/2)c/a, since a = c (because its equal lateral) we are left with cos(x)=(1/2) which means x = 60 degrees. this can be applied to all three angles, which shows that all three angles are 60 degrees.
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We have now shown that all equal lateral triangles are similar because they all have proportional sides, and they all have equal angles.
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Some equilateral triangles are not isosceles?
All isosceles triangles are not equilateral triangles
Are all equilateral triangles acute triangles?
Yes all equilateral triangles are acute triangles, but not all acute triangle are equilateral triangles.
Are all equilateral triangles are congruent?
no. if one triangles sides are all 2 and one triangles sides are all 3 then they are not congruent
All isosceles triangles are also equilateral triangles?
No, all isosceles triangles are not equilateral triangles. An isosceles triangle is a triangle that has two sides of equal length. An equilateral triangle is a triangle that has all three sides of equal length. Therefore, it is possible for a triangle to be isosceles but not equilateral. For example, a triangle with sides of lengths 3, 3, and 4 is an isosceles triangle, but it is not an equilateral triangle because all its sides do not have the same length. On the other hand, all equilateral triangles are also isosceles triangles because they have two sides of equal length. My recommendation ʜᴛᴛᴘꜱ://ᴡᴡᴡ.ᴅɪɢɪꜱᴛᴏʀᴇ24.ᴄᴏᴍ/ʀᴇᴅɪʀ/372576/ꜱᴀɪᴋɪʀᴀɴ21ᴍ/
What is the difference between an equilateral triangle and scalene triangle?
Equilateral triangles have all the same side lengths and scalene triangles have no similar side lengthsAn equilateral triangle has 3 equal sides whereas a scalene triangle has 3 unequal sides
Two equilateral triangles are sometimes similar?
Two equilateral triangles are always similar!
Some equilateral triangles are not isosceles?
All isosceles triangles are not equilateral triangles
Are all pentagons are similar?
NO! Only REGULAR Pentagons. All equilateral triangles are similar!!!
Are all equilateral triangles acute triangles?
Yes all equilateral triangles are acute triangles, but not all acute triangle are equilateral triangles.
Are some isosceles triangles equilateral triangles?
All isosceles triangles are not equilateral triangles
All equilateral triangles are similar true or false?
True as true can be.
Which two words describe all equiangular triangles?
equilateral and similar
Are all equilateral triangles are congruent?
no. if one triangles sides are all 2 and one triangles sides are all 3 then they are not congruent
Are all equilateral triangles also isoscelles triangles?
Yes. But not all isosceles triangles are equilateral.
Are Triangles equilateral triangles?
Triangles are equilateral triangles only when all of their 3 sides are equal in lengths.
Are equilateral triangle are acute?
Yes all equilateral triangles are acute triangles, but not all acute triangle are equilateral triangles.
Are two equilateral triangles sometimes always or never similar to each other?
Since triangles have three sides and must have interior angles equal to pi or 180o, the three interior angles in all equilateral triangles will be pi/3 or 60o.However, equilateral triangles must also have equal side lengths. Since equilateral triangles with interior angles of 60o will not necessarily have the same side lengths, two equilateral triangles will sometimes be similar to each other.
