Let $a \equiv 1 \pmod{4}$. Find the value of $6a + 5 \pmod{4}$Express your answer as a residue between 0 and the modulus.
Can you translate your question into ordinary symbols, so that we can understand your question? Most of us can't read LaTex!. Thanks.
+26387 Let
\(a \equiv 1 \pmod{4}\).
Find the value of
\(6a + 5 \pmod{4}\)
Express your answer as a residue between 0 and the modulus.
\(\begin{array}{|rcll|} \hline && 6a + 5 \pmod{4} \\ &\equiv& 6a + 5 -4 \pmod{4} \\ &\equiv& 6a + 1 \pmod{4} \quad & | \quad a \equiv 1 \pmod{4} \\ &\equiv& 6\cdot 1 + 1 \pmod{4} \\ &\equiv& 7 -1\cdot 4 \pmod{4} \\ &\equiv& 7 -4 \pmod{4} \\ &\equiv& 3 \pmod{4} \\ \hline \end{array}\)
The answer is 3.
