An isosceles triangle may be right or acute but never obtuse.
a. true
b. false

An isosceles triangle is a triangle in which the two sides of the polygon are equal as well as the angles opposite to these sides are also congrunet. In this case, an isosceles triangle could have 45-45-90 angles which means it can be a right angle. An obtuse triangle has angle greater than 90 which can be truly possible for isosceles triangles. Answer then is false.