a.
\(\dfrac{3}{4}x+\dfrac{2}{5}=\dfrac{-1}{6}\)
\(\dfrac{3}{4}x=\dfrac{-1}{6}-\dfrac{2}{5}\)
\(\dfrac{3}{4}x=-\dfrac{17}{30}\)
\(x=-\dfrac{17}{30}:\dfrac{3}{4}\)
\(x=-\dfrac{34}{45}\)
b.
\(\dfrac{1}{4}-\dfrac{7}{10}x=1\dfrac{3}{4}\)
\(\dfrac{1}{4}-\dfrac{7}{10}x=\dfrac{7}{4}\)
\(\dfrac{7}{10}x=\dfrac{1}{4}-\dfrac{7}{4}\)
\(\dfrac{7}{10}x=-\dfrac{3}{2}\)
\(x=-\dfrac{3}{2}:\dfrac{7}{10}\)
\(x=-\dfrac{15}{7}\)
c.
\(x:\dfrac{3}{2}-\dfrac{1}{2}=\dfrac{-5}{4}\)
\(x:\dfrac{3}{2}=\dfrac{-5}{4}+\dfrac{1}{2}\)
\(x:\dfrac{3}{2}=-\dfrac{3}{4}\)
\(x=-\dfrac{3}{4}\times\dfrac{3}{2}\)
\(x=-\dfrac{9}{8}\)
d.
\(\left(2\dfrac{4}{5}x+32\right):\dfrac{2}{3}=90\)
\(\left(\dfrac{14}{5}x+32\right):\dfrac{2}{3}=90\)
\(\dfrac{14}{5}x+32=90\times\dfrac{2}{3}\)
\(\dfrac{14}{5}x+32=60\)
\(\dfrac{14}{5}x=60-32\)
\(\dfrac{14}{5}x=28\)
\(x=28:\dfrac{14}{5}\)
\(x=10\)
