Answer: 1
Step-by-step explanation:
[tex]\begin{array}{c|c}4& 2 \\2& 2 \\ \bf 1 \end {array }[/tex] [tex]\begin{array}{c|c}9&3\\3&3\\\bf 1 \end {array }[/tex]
Then HFC(4 ; 9 )= 1