Question

triangle def is congruent to △def by the sss theorem. which single rigid transformation is required to map △def onto △def? dilation translation rotation reflection

Explanation:

• Dilation is not a rigid transformation as it changes the size of the figure.
• Translation moves the figure without rotation or reflection. But here, the orientation of the triangle relative to point \(E\) has changed.
• Rotation would require a center of rotation and a certain angle, but the figure shows a mirror - like orientation.
• Reflection is a rigid transformation that flips a figure over a line. In this case, reflecting \(\triangle DEF\) over a line (possibly a line passing through \(E\)) would map it onto \(\triangle D'EF'\) as per the SSS congruence (since reflection preserves side lengths).

Answer:

reflection