Question

tìm x, biết

a) x = 1 phần 2 + 3 phần 4

b) x phần 5 = 5 phần 6 - 19 phần 30

c) x = 1 phần 2 - 2 phần 3 

d) x phần 3 = 2 phần 3 trừ 1 phần 7

Answer 1

Không rõ đề lắm bạn ơi

Answer 2

câu hỏi của bạn có sai ko ạ

 

 

Answer 3

a) \(x=\dfrac{1}{2}+\dfrac{3}{4}\)

\(\Rightarrow x=\dfrac{2}{4}+\dfrac{3}{4}\\ \Rightarrow x=\dfrac{5}{4}\)

b) \(\dfrac{x}{5}=\dfrac{1}{2}-\dfrac{2}{3}\)

\(\Rightarrow\dfrac{x}{5}=\dfrac{3}{6}-\dfrac{4}{6}\)

\(\Rightarrow\dfrac{x}{5}=-\dfrac{1}{6}\)

\(\Rightarrow x=-\dfrac{1}{6}.5\)

\(\Rightarrow x=-\dfrac{5}{6}\)

c) \(x=\dfrac{1}{2}-\dfrac{2}{3}\)

\(\Rightarrow x=\dfrac{3}{6}-\dfrac{4}{6}\)

\(\Rightarrow x=-\dfrac{1}{6}\)

d) \(\dfrac{x}{3}=\dfrac{2}{3}-\dfrac{1}{7}\)

\(\Rightarrow\dfrac{x}{3}=\dfrac{14}{21}-\dfrac{3}{21}\)

\(\Rightarrow\dfrac{x}{3}=\dfrac{11}{21}\)

\(\Rightarrow x=\dfrac{11}{21}.3\)

\(\Rightarrow x=\dfrac{33}{21}\)

Answer 4

a,\(x=\dfrac{1}{2}+\dfrac{3}{4}\Leftrightarrow x=\dfrac{2}{4}+\dfrac{3}{4}\Leftrightarrow x=\dfrac{5}{4}\)

b,\(\dfrac{x}{5}=\dfrac{5}{6}-\dfrac{19}{30}\Leftrightarrow\dfrac{x}{5}=\dfrac{1}{5}\Rightarrow5x=5\Leftrightarrow x=1\)

c,\(x=\dfrac{1}{2}-\dfrac{2}{3}\Leftrightarrow x=\dfrac{3}{6}-\dfrac{4}{6}\Leftrightarrow x=-\dfrac{1}{6}\)

d,\(\dfrac{x}{3}=\dfrac{2}{3}-\dfrac{1}{7}\Leftrightarrow\dfrac{x}{3}=\dfrac{11}{21}\Rightarrow21x=33\Leftrightarrow x=\dfrac{33}{21}=\dfrac{11}{7}\)

Answer 5

a: Ta có: \(x=\dfrac{1}{2}+\dfrac{3}{4}\)

nên \(x=\dfrac{2}{4}+\dfrac{3}{4}\)

hay \(x=\dfrac{5}{4}\)

c: Ta có: \(x=\dfrac{1}{2}-\dfrac{2}{3}\)

nên \(x=\dfrac{3}{6}-\dfrac{4}{6}\)

hay \(x=-\dfrac{1}{6}\)