Ta có:
31(xyzt+xy-xt-zt-1)=40(yzt-y-t)
\(\Rightarrow\frac{xyzt-xy+xt+zt+1}{yzt+y+t}\)\(=\frac{40}{31}\)
\(\Rightarrow\frac{x\left(yzt+y+t\right)+zt+1}{yzt+y+t}\)\(=\frac{40}{31}\)
\(\Rightarrow\frac{zt+1}{yzt+y+t}=\frac{40}{31}\)
còn dài lắm bạn mở câu hỏi tương tự nha