Answer:
[tex]\large\boxed{GCF(40s^3t^5,\ 2s^4t^4,\ 14s^6t^6)=2s^3t^4}[/tex]
Step-by-step explanation:
[tex]40s^3t^5=\boxed2\cdot2\cdot2\cdot5\cdot \boxed{s\cdot s\cdot s}\cdot \boxed{t\cdot t\cdot t\cdot t}\cdot t\\\\2s^4t^4=\boxed2\cdot \boxed{s\cdot s\cdot s}\cdot s\cdot \boxed{t\cdot t\cdot t\cdot t}\\\\14s^6t^6=\boxed2\cdot7\cdot \boxed{s\cdot s\cdot s}\cdot s\cdot s\cdot s\cdot \boxed{t\cdot t\cdot t\cdot t}\cdot t\cdot t\\\\GCF(40s^3t^5,\ 2s^4t^4,\ 14s^6t^6)=\boxed2\cdot \boxed{s\cdot s\cdot s}\cdot\boxed{t\cdot t\cdot t\cdot t}=2s^3t^4[/tex]
