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No. All equilateral and equiangular triangles are acute. (All angles are equal to 60°, which is less than a right angle [90°]); however, the converse (which is what was asked) is not true.
A triangle can have all three angles be less than 90°, but not be an equilateral triangle.
An example is a triangle with angles of 80°, 60°, and 40°. It is scalene and acute.
From the Law of Sines: a/sin(A) = b/sin(B) = c/sin(C), you can show that sin(80°) does not equal sin(60°) or sin(40°), so none of sides a, b, and c, are equal.
You could have an acute isosceles triangle like: 80°, 80° and 20° angles, as another example. From the Law of Sines, you can show that two of the sides are equal, but the third side (opposite the 20° angle) is not equal to either of the other 2.
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what- an equilateral triangle is used in a tent design. is this statement true or false the triangle is equilateral?
true
An equilateral triangle is a special case of an isosceles triangle?
true
Ture or false is An equilateral triangle a special case of an isosceles triangle?
true
True or false a triangle can be both right-angled and equilateral?
False. All angles of an equilateral triangle are 60 degrees.
Is a triangle a small regular polygon?
A regular polygon is any polygon that has sides which are the same length and angles whose measures are equal. An equilateral triangle (also equiangular triangle) is a regular polygon. Other isosceles triangles (equilateral triangles are isosceles, but they are an exception) and scalene triangles are not regular polygons. A side note: Only in a triangle is a polygon regular solely if it is equilateral. (Since an equilateral triangle is equiangular as well). This is NOT always true in other polygons, like quadrilaterals, where it can be equilateral but not necessarily equiangular (a rhombus) or equiangular but not equilateral (a rectangle).
what- an equilateral triangle is used in a tent design. is this statement true or false the triangle is equilateral?
true
Are equilateral triangle is acute is this true?
Yes. Equilateral means all equal sides and angles. Since the sum of the angles in a triangle must add up to 180 degrees and each angle is equal then each angle is 60 degrees which is smaller than 90 degrees and therefore, acute.
Are the halve of an equilateral triangle symmetrical?
A equilateral triangle has 3 lines of symmetry and so it is true.
What statement sometimes true about the relationship between acute triangles and isosceles triangle?
The two acute angles are always equal.
An equilateral triangle is a special case of an isosceles triangle?
true
All equilateral triangles are acute and isosceles?
the answer is true, apex
An equilateral triangle has at least two sides that are equal true or false?
False...an equilateral triangle has 3 equal sides.
Ture or false is An equilateral triangle a special case of an isosceles triangle?
true
How many sides does an equilateral triangle have?
All triangles have exactly three sides. This is true whether the triangle is equilateral or not. If the triangle is equilateral, then the three sides will all be equal in length.All triangles have three sides.
True or false a triangle can be both right-angled and equilateral?
False. All angles of an equilateral triangle are 60 degrees.
Can a triangle have both an acute an a right angle true or false?
It is true because a triangle with a right angle and two acute angles is a right angle triangle.
Is a triangle a small regular polygon?
A regular polygon is any polygon that has sides which are the same length and angles whose measures are equal. An equilateral triangle (also equiangular triangle) is a regular polygon. Other isosceles triangles (equilateral triangles are isosceles, but they are an exception) and scalene triangles are not regular polygons. A side note: Only in a triangle is a polygon regular solely if it is equilateral. (Since an equilateral triangle is equiangular as well). This is NOT always true in other polygons, like quadrilaterals, where it can be equilateral but not necessarily equiangular (a rhombus) or equiangular but not equilateral (a rectangle).
