Congruency is an idea that means, regardless of their location or position or direction, two or more geometric figures have the same shape and size. When two or more things have congruency, they are called congruent.
Operations that result in congruent figures include:
Rotate
Reflect
Translate
Operations that result in congruent figures DO NOT include:
Dilation
Interestingly, dilating a shape by a certain scale figure will not produce congruent shapes. But the shapes will be similar and preserve side/angle ratios.
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