[tex](6A)_{16}=6\cdot 16+10=106[/tex]
[tex](211)_x=2\cdot x^2+1\cdot x + 1=106[/tex]
[tex]2 x^2+ x + 1-106=0[/tex]
[tex]2\cdot x^2+ x -105=0[/tex]
[tex]\Delta=1^2-4\cdot 2\cdot (-105)=1+840=841=29^2[/tex]
[tex]x=\dfrac{-1+29}{2\cdot 2}=\dfrac{28}{4}=7[/tex]
The value of base x is equal to 7.
