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.
Yes, Karen is correct. Every equilateral triangle has all three angles equal to 60 degrees, which are all acute angles (less than 90 degrees). Therefore, it is accurate to say that every equilateral triangle is acute.
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False. All angles of an equilateral triangle are 60 degrees.
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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.
A equilateral triangle has 3 lines of symmetry and so it is true.
The two acute angles are always equal.
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the answer is true, apex
False...an equilateral triangle has 3 equal sides.
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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.
False. All angles of an equilateral triangle are 60 degrees.
It is true because a triangle with a right angle and two acute angles is a right angle triangle.
An obtuse triangle has 1 obtuse angle and 2 acute angles which add up to 180 degrees.