a. x + \(\dfrac{3}{7}\)= \(\dfrac{2}{5}:\dfrac{18}{25}=>x+\dfrac{3}{7}=\dfrac{2}{5}\)x\(\dfrac{35}{18}=>x+\dfrac{3}{7}=\dfrac{7}{9}\)
=> x = \(\dfrac{7}{9}-\dfrac{3}{7}=\dfrac{49}{63}-\dfrac{27}{63}=\dfrac{22}{63}\)
b. \(x\) x \(\dfrac{5}{9}\)= \(\dfrac{4}{5}-\dfrac{1}{3}\)
=> \(x\) x \(\dfrac{5}{9}\)= \(\dfrac{12}{15}-\dfrac{5}{15}=>x\) x \(\dfrac{5}{9}\)= \(\dfrac{7}{15}\)
=> x = \(\dfrac{7}{15}:\dfrac{5}{9}\)
=> x = \(\dfrac{21}{25}\)
a,x + 3/7 = 2/5 : 18/35
x + 3/7 = 7/9
x = 7/9 - 3/7
x = 22/63
vậy x = ...
b, X x 5/9 = 4/5 - 1/3
X x 5/9 = 7/15
X = 7/15 : 5/9
X = 21/25
vậy X = ...