Congruency

 

5.1

 Congruency

 
What is congruency?
 
Two figures or objects are congruent if they have the same shape and size regardless of their position and arrangement.
 
 
Example 1
 
Determine whether the following shapes are congruent.
 
 
Solution:
 

\[\begin{aligned} BC &= \sqrt{5^2+12^2}\\ &=13\text{ cm}\\ &=RQ.\\\\ \angle PRQ &= 180^\circ - 90^\circ - 22.6^\circ\\ &=67.4^\circ\\ &=\angle ABC. \end{aligned}\]

The measurements of all corresponding sides and angles are equal.
Both shapes are congruent.