Question

Tìm x biết:

(4,5-2x).1\(\dfrac{4}{7}\)=\(\dfrac{11}{4}\)

Tifmn số nguyên x biết:

4\(\dfrac{1}{3}\left(\dfrac{1}{6}-\dfrac{1}{2}\right)< _-x< _-\dfrac{2}{3}.\left(\dfrac{1}{3}-\dfrac{1}{2}-\dfrac{3}{4}\right)\)

Answer 1

Tìm x biết:

\(\left(4,5-2x\right).1\dfrac{4}{7}=\dfrac{11}{4}\)

\(\Leftrightarrow\left(4,5-2x\right)=\dfrac{11}{4}:1\dfrac{4}{7}\)

\(\Leftrightarrow4,5-2x=\dfrac{7}{4}\)

\(\Leftrightarrow2x=4,5-\dfrac{7}{4}\)

\(\Leftrightarrow2x=\dfrac{11}{4}\)

Vậy \(x=\dfrac{11}{8}\)

Tìm số nguyên x biết:

Theo đề bài, ta có:

\(4\dfrac{1}{3}\left(\dfrac{1}{6}-\dfrac{1}{2}\right)\le x\le\dfrac{2}{3}\left(\dfrac{1}{3}-\dfrac{1}{2}-\dfrac{3}{4}\right)\)

\(\Leftrightarrow-\dfrac{13}{9}\le x\le-\dfrac{11}{18}\) hay \(-\dfrac{26}{18}\le x\le-\dfrac{11}{18}\)

\(\Leftrightarrow-1,\left(4\right)\le x\le-0,6\left(1\right)\)

Mà \(x\in Z\) nên x=-1

Vậy x = -1

Answer 2

1 ) \(\left(4,5-2x\right).1\dfrac{4}{7}=\dfrac{11}{4}\)

\(\Leftrightarrow\left(4,5-2x\right).\dfrac{11}{7}=\dfrac{11}{4}\)

\(\Leftrightarrow4,5-2x=\dfrac{11}{4}:\dfrac{11}{7}=\dfrac{11}{4}.\dfrac{7}{11}=\dfrac{7}{4}\)

\(\Leftrightarrow2x=2,75\)

\(\Leftrightarrow x=1,375\)

2 ) Đáp án x = 0 nhé !!

Cậu chỉ cần lấy số nguyên giữa 2 số thập phân .