Respuesta :

Answer:

The value of given expression is 0, where  m=21 and n=12.

Step-by-step explanation:

The given expression is

[tex]\dfrac13m-1-\dfrac12n[/tex]

substitute m=21 and n=12 in the above expression.

[tex]\dfrac13m-1-\dfrac12n=\dfrac13(21)-1-\dfrac12(12)[/tex]

[tex]\dfrac13m-1-\dfrac12n=7-1-6[/tex]

[tex]\dfrac13m-1-\dfrac12n=7-7[/tex]

[tex]\dfrac13m-1-\dfrac12n=0[/tex]

Therefore the value of given expression is 0, where  m=21 and n=12.