That it has a 90 degree angle and two equal 45 degree angles
True
The base angles are always congruent.
The two acute angles are always equal.
True or False, depending on your definition of isosceles triangles!Actually, whether your answer is true or false depends upon your definition of an isosceles triangle. Some mathematicians define an isosceles triangle as one with at least two sides, while others define an isosceles triangle as one with exactly two sides. The latter definition is the more generally accepted one. Since an equilateral triangle has three, not exactly two congruent sides, people using the second definition of isosceles triangles would say that the statement is false, not true.False because an equilateral triangle has 3 equal sides whereas an isosceles triangle has only 2 equal sides
That it has a 90 degree angle and two equal 45 degree angles
It is true.
True
It is a right angle triangle or an isosceles right angle triangle
The base angles are always congruent.
false
An obtuse triangle or a right angle triangle. An equilateral is definitely an isoceles triangle * * * * * Not true. An obtuse or right angled triangles can be isosceles. It depends on the sizes of the two smaller angles. An isosceles triangle has two equal angles so a triangle with angles of size [A, (180-A)/2, (180-A)/2] degrees where 90 < A < 180 degrees would be an obtuse angled isosceles triangle. A triangle with angles of size (90, 45, 45) degrees is a right angled isosceles triangle.
The converse is, "If a triangle is isosceles, then it is equilateral." Neither is true.
The two acute angles are always equal.
This is a true statement that defines a triangle in geometry. However, there are many different types of triangles, such as obtuse, acute, scalene, right, equilateral, and isosceles triangles.
true
Not true. A triangle with angles of 90, 45 and 45 is a right angled isosceles triangle. If you take a square piece of paper and fold it in half - from corner to corner - you will get this shape.