Answer:
[tex]\frac{4}{9}[/tex]
Step-by-step explanation:
12+m^2/n-n^4
12+(10)^2/4-(4)^4
12+100/4-256
112/-252
[tex]\frac{4}{9}[/tex]
[tex]\\ \rm\hookrightarrow 12+m^2/n-n^4[/tex]
[tex]\\ \rm\hookrightarrow 12+10^2/2-2^4[/tex]
[tex]\\ \rm\hookrightarrow 112/-14[/tex]
[tex]\\ \rm\hookrightarrow -7[/tex]