Question

Bài 7 tìm x
1/4(8/3-x)+1/5=-3/4(1/2-1)
3/2(x-4/9)=4/7(7-1/4)-1/3

Answer 1

a)

\(\dfrac{1}{4}\cdot\left(\dfrac{8}{3}-x\right)+\dfrac{1}{5}=-\dfrac{3}{4}\cdot\left(\dfrac{1}{2}-1\right)\)

\(\dfrac{1}{4}\cdot\left(\dfrac{8}{3}-x\right)+\dfrac{1}{5}=\dfrac{3}{8}\)

\(\dfrac{1}{4}\cdot\left(\dfrac{8}{3}-x\right)=\dfrac{3}{8}-\dfrac{1}{5}\)

\(\dfrac{1}{4}\cdot\left(\dfrac{8}{3}-x\right)=\dfrac{7}{40}\)

\(\dfrac{8}{3}-x=\dfrac{7}{10}\)

\(x=\dfrac{59}{30}\)

b)

\(\dfrac{3}{2}\cdot\left(x-\dfrac{4}{9}\right)=\dfrac{74}{21}\)

\(x-\dfrac{4}{9}=\dfrac{148}{63}\)

\(x=\dfrac{176}{63}\)

Answer 2

\(\dfrac{1}{4}.\left(\dfrac{8}{3}-x\right)+\dfrac{1}{5}=\dfrac{3}{8}\)

=>\(\dfrac{1}{4}.\left(\dfrac{8}{3}-x\right)=\dfrac{7}{40}\)

=>\(\dfrac{8}{3}-x=\dfrac{7}{40}:\dfrac{1}{4}\)

=>\(\dfrac{8}{3}-x=\dfrac{7}{10}\)

=>x=\(\dfrac{8}{3}-\dfrac{7}{10}\)

=>x=\(\dfrac{59}{30}\)

b=>,\(\dfrac{3}{2}.\left(x-\dfrac{4}{9}\right)=\dfrac{74}{21}\)

=>\(x-\dfrac{4}{9}=\dfrac{74}{21}:\dfrac{3}{2}\)

=>\(x-\dfrac{4}{9}=\dfrac{148}{63}\)

=>x=\(\dfrac{148}{63}+\dfrac{4}{9}\)

=>x=\(\dfrac{176}{63}\)