Question

5分之4+x-五分之4乘x等于20分之21 \(^o^)/~\(≧▽≦)/~

Answer 1

4/5+x-(4/5)x=21/20

4/5+[x-(4/5)x]=21/20

4/5+(1/5)x=21/20

(1/5)x=21/20-4/5

(1/5)x=1/4

x=1/4×5

x=5/4