posted by Becky .
Which one of the following pairs of triangle must be similar?
a) two isosceles triangles with congruent vertex angles
b) two right triangles
c) two scalene triangles with congruent bases
d) two obtuse triangles
a) if the two vertex angles are the same then the other two angles of both both triangles have to be the same and identical since all three have to add to 180 then since the two base angles are the same the sides opposite them are congruent and the two triangles are similar be SAS(side angle side)