Question

Tìm x trong các đẳng thức sau:

a) x+3/5 = 1/4 b) 2/3-x=\(1\frac{4}{7}-2\frac{3}{4}\)

Answer 1

a)

\(x+\frac{3}{5}=\frac{1}{4}\)

\(\Rightarrow x=-\frac{7}{20}\)

Vậy ........

b)

\(\frac{2}{3}-x=1\frac{4}{7}-2\frac{3}{4}\)

\(\Rightarrow\frac{2}{3}-x=\frac{11}{7}-\frac{11}{4}\)

\(\Rightarrow\frac{2}{3}-x=-\frac{33}{28}\)

\(\Rightarrow x=\frac{75}{28}\)

Answer 2

a) Theo quy tắc chuyển vế ta có:

\(x+\frac{3}{5}=\frac{1}{4}\Rightarrow x=\frac{1}{4}-\frac{3}{5}\)

\(x=\frac{1}{4}+\frac{\left(-3\right)}{5}=\frac{5+4.\left(-3\right)}{20}\\ \Rightarrow x=\frac{-7}{20}\)

b) Theo quy tắc chuyển vế ta có:

\(\frac{2}{3}-x=1\frac{4}{7}-2\frac{3}{4}\Rightarrow\frac{2}{3}=1\frac{4}{7}-2\frac{3}{4}+x\\ \Rightarrow x=\frac{2}{3}-1\frac{4}{7}+2\frac{3}{4}=\frac{2}{3}-\frac{11}{7}+\frac{11}{4}=\frac{56-132+231}{84}\\ x=\frac{155}{84}=1\frac{71}{84}\)

Answer 3

a) x + \(\frac{3}{5}\) = \(\frac{1}{4}\)

x = \(\frac{1}{4}-\frac{3}{5}\)

x = \(\frac{-7}{20}\)

b) \(\frac{2}{3}\) - x = \(1\frac{1}{4}\) - \(2\frac{3}{4}\)

\(\frac{2}{3}-x=\frac{-3}{2}\)

x = \(\frac{2}{3}-\frac{-3}{2}\)

x =\(\frac{13}{6}\)

Answer 4

sorry , câu b mk chép sai đề

Answer 5

a) x+3/5 = 1/4

x + 3/5 =0,25

x =0,25 -3/5

x =0,25-0,6

x = -0,35

câu b mik ko biết hihi