Question

[hello Đạt]

 

Answer 1

[Toru]

\(\dfrac{45\%}{x-1,25}-2\dfrac{3}{8}=-1\dfrac{31}{40}\)

\(\Rightarrow\dfrac{0,45}{x-1,25}-\dfrac{19}{8}=-\dfrac{71}{40}\)

\(\Rightarrow\dfrac{0,45}{x-1,25}=-\dfrac{71}{40}+\dfrac{19}{8}\)

\(\Rightarrow\dfrac{0,45}{x-1,25}=\dfrac{3}{5}\)

\(\Rightarrow3\left(x-1,25\right)=5\cdot0,45\)

\(\Rightarrow3\left(x-1,25\right)=\dfrac{9}{4}\)

\(\Rightarrow x-1,25=\dfrac{9}{4}:3\)

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

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

\(\Rightarrow x=\dfrac{8}{4}=2\)

Answer 2

[Toru]

Bạn xem lại dòng thứ 3 nhé!