b, \(\frac{72-x}{3}=\frac{x-18}{5}\)
\(\Rightarrow\left(72-x\right).5=\left(x-18\right).3\)
\(\Rightarrow72.5-5x=3x-18.3\)
\(\Rightarrow360-5x=3x-54\)
\(\Rightarrow360+54=3x+5x\)
\(\Rightarrow414=8x\)
\(\Rightarrow x=414:8\)
\(\Rightarrow x=51,75\)
Vậy \(x=51,75\)
a, \(3\frac{4}{5}:2x=0,25:2\frac{2}{3}\)
\(\frac{19}{5}:2x=\frac{1}{4}:\frac{8}{3}\)
\(\frac{19}{5}:2x=\frac{3}{32}\)
\(2x=\frac{19}{5}:\frac{3}{32}\)
\(2x=\frac{608}{15}\)
\(x=\frac{304}{15}\)
Thay x vào biểu thức thì nó không có bằng nhau. Bạn xem lại đề nha.
b) \(\frac{72-x}{3}=\frac{x-18}{5}\)
\(\Rightarrow\left(72-x\right).5=\left(x-18\right).3\)
\(\Rightarrow360-5x=3x-54\)
\(\Rightarrow360+54=3x+5x\)
\(\Rightarrow414=8x\)
\(\Rightarrow x=414:8\)
\(\Rightarrow x=\frac{207}{4}\)
Vậy \(x=\frac{207}{4}.\)
Chúc bạn học tốt!