a: =>5/7:x=3/7
=>x=5/7:3/7=5/7x7/3=5/3
b: =>4/7x=1/5+2/3=3/15+10/15=13/15
=>x=13/15:4/7=13/15x7/4=91/60
c: =>17/33x=1
=>x=33/17
\(a,\dfrac{4}{7}+\dfrac{5}{7}:x=1\)
\(\dfrac{5}{7}:x=1-\dfrac{4}{7}\)
\(\dfrac{5}{7}:x=\dfrac{3}{7}\)
\(x=\dfrac{5}{7}:\dfrac{3}{7}\)
\(x=\dfrac{5}{7}\times\dfrac{7}{3}\)
\(x=\dfrac{5}{3}\)
\(b,\dfrac{4}{7}x-\dfrac{2}{3}=\dfrac{1}{5}\)
\(\dfrac{4}{7}x=\dfrac{1}{5}+\dfrac{2}{3}\)
\(\dfrac{4}{7}x=\dfrac{13}{15}\)
\(x=\dfrac{13}{15}:\dfrac{4}{7}\)
\(x=\dfrac{13}{15}\times\dfrac{7}{4}\)
\(x=\dfrac{91}{60}\)
\(c,\left(\dfrac{2}{11}+\dfrac{1}{3}\right)x=\left(\dfrac{1}{7}-\dfrac{1}{8}\right).56\)
\(\dfrac{17}{33}x=1\)
\(x=1:\dfrac{17}{33}\)
\(x=1\times\dfrac{33}{17}\)
\(x=\dfrac{33}{17}\)
