a: 25-3x=37
=>3x=25-37=-12
=>\(x=-\dfrac{12}{3}=-4\)
b: \(\dfrac{x}{18}=-\dfrac{5}{6}\)
=>\(x=-\dfrac{5}{6}\cdot18\)
=>x=-15
c: \(x-\dfrac{3}{4}=\dfrac{5}{8}\cdot\dfrac{-2}{3}\)
=>\(x-\dfrac{3}{4}=\dfrac{-10}{24}=-\dfrac{5}{12}\)
=>\(x=\dfrac{3}{4}-\dfrac{5}{12}=\dfrac{9}{12}-\dfrac{5}{12}=\dfrac{4}{12}=\dfrac{1}{3}\)