From the proof of modular congruence below, it has been shown that;
41 ≡ 21 (mod 3).
<h3>How to Solve Modular Arithmetic?</h3>
We want to use the definition of modular congruence to	prove that;
41 is congruent to 21 (mod 3) i.e if a ≡ b (mod m) then b ≡ a (mod m).
We are trying to prove that modular congruence mod 3 is a symmetric	relation on the integers.
First, if we recall the definition of	modular congruence:	
For integers a, b and positive integer m,  
a ≡ b (mod m) if and only if m|a–b
Suppose	41 ≡ 21 (mod 3).
Then, by	definition, 3|41–21,	so there is an integer k such that	41 – 21 =	3k.
Thus;	
–(41 – 21) = –3k
So
21 – 41 =	3(–k)
This	shows that 3|21 – 41.
Thus;
21 ≡ 41 (mod 3) and the	proof is complete
Read more about Modular Arithmetic at; brainly.com/question/16032865
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