What Are Congruent Figures?
Congruent figures are exactly the same shape, and they’re exactly the same size.
In the below figure 1, one triangle points up, while the other points down. However, if you were to measure them, you’d discover that the corresponding sides of both triangles are exactly the same. In fact, the second triangle is the same as the first; it’s just been rotated. So, these shapes are congruent.
In second example , see figure 2, these are both squares, but one is much smaller than the other. Although they’re the same shape but these two figures aren’t the same size. Therefore, these squares are incongruent figure.
Class 10 Triangles Exercise 6.1 Introduction (Brief Synopsis) of

Congruent figure and

Similar figure
Solution/definition is given in the below image,
Click here to see the step by step explanation.

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