Isoceles Triangle
The answer depends on what shape the question is about.
If all side lengths are changed so the new shape is proportionately equal, the angles don't change. But if it's not proportion. equal, then the angles will be different
An EQUILATERAL TRIANGLE
regular pentagon maybe maybe not
Rectangle.
it has to have equal angles, not side lengths. otherwise it would just be two of the same shape
If a shape has equal angles and side lengths then it is known as a regular polygon
An equilateral triangle has 3 equal interior angles that add up to 180 degrees
square
the shape is a regular shape if it has all the same angles and side lengths.
There are exactly 3 equal angles (of 60o) and three equal sides in any equilateral triangle.
A symmetric trapezium.