Is it possible for an isosceles triangle to also be a right triangle?
Yes - a right isosceles triangle would have base angles of 45 degrees.[br][br]So its 3 angles would be:[br]90 degrees[br]45 degrees[br]45 degrees
Is it possible for an isosceles triangle to be obtuse?
Yes - if one angle is big, it just means the two base angles would be small.[br][br]One example:[br]140 degrees[br]20 degrees[br]20 degrees
Is it possible for an isosceles triangle to be acute?
Yes - as long as the two base angles aren't so small that the remaining angle is obtuse.[br][br]For example:[br]80 degrees[br]50 degrees[br]50 degrees
Is it possible for an isosceles triangle to be equilateral/equiangular?
Yes! In fact, ALL equilateral triangles are ALSO isosceles, because the isosceles triangle just needs two or more equal sides (or angles).
Equilateral Triangles
Can an equilateral triangle be:[br][br]Right?[br]Acute?[br]Obtuse?
No, yes, no.[br][br]An equilateral triangle can only be an ACUTE triangle - since all the sides are the same, all the angles have to be the same (always 60 degrees!)
Scalene Triangles
Can a scalene triangle be:[br][br]Right?[br]Acute?[br]Obtuse?
Yes to all of them! Since scalene triangles just have to have all sides of different lengths, all angles will be different too - anything is possible!