Yes, due to the definition of congruent figures.
Figures are congruent if and only if they are related by a translation, reflection, or rotation, or some combination of these transformations.
only if the mirror is flat
no
rhombus
A regular polygon.
translation
No its not
Yes
Figures are congruent if and only if they are related by a translation, reflection, or rotation, or some combination of these transformations.
A translation, a reflection and a rotation
Yup
only if the mirror is flat
no
rhombus
A regular polygon.
Yes, they are.
It will be as you term it 'horizontal stretch' in which the figure is enlarged or reduced in size.