there are three angles on an isosceles triangle
An acute scalene triangle has none. An acute isosceles triangle has one and an [acute] equilateral has three.
It doesn't matter if a triangle is isosceles, scalene, obtuse, acute... There are always 3 angles in a triangle (which add up to 180).
3
One acute angle
There is 180 degrees in every triangle.
3 lines * * * * * None if it is acute angled scalene One if it is acute angled isosceles and Three if it is equilateral.
there is 1 line of simmetry An equilateral triangle has three. An acute isosceles has one and an acute scalene has none.
Triangles can be classified based on their sides and angles. Based on sides, triangles can be equilateral (all sides are equal), isosceles (two sides are equal), or scalene (no sides are equal). Based on angles, triangles can be acute (all angles are less than 90 degrees), obtuse (one angle is greater than 90 degrees), or right (one angle is exactly 90 degrees).
Im assuming your question is How many acute angles does the isosceles triangle has. It should have 2
None. If there was a right angle then it would not be called an acute triangle.
There are triangles that are named for relationships of their side lengths: scalene has no equal sides Isosceles has 2 equal sides, and equilateral has all 3 sides equal. Then there are names for relationship of angles. Acute has all 3 angles less than a right angle (90°). Right has one angle is a right angle (90°). Obtuse has one angle greater than 90° but less than 180°. An equilateral triangle has all three angles 60°, so it is also acute. An acute triangle can be scalene or isosceles, as well. A right triangle can also be either scalene or isosceles. An obtuse triangle can also be scalene or isosceles.