Question

giải hộ mik vs ak.,giải theo công thức lớp 7 vs ak

```plaintext
BÀI TẬP VỀ NHÀ

Bài 1. Tìm x biết:

1) x + \frac{3}{4} = \frac{4}{3}
2) x - \frac{3}{5} = \frac{4}{15}
3) -x - \frac{2}{15} = \frac{7}{10}
4) \frac{7}{9} - x = \frac{1}{12}
5) \frac{3}{4} x = \frac{-5}{6}
6) \left( x + \frac{2}{3} \right) \cdot \frac{4}{5} = \frac{-8}{15}
7) \frac{6}{7} : x = \frac{-8}{21}
8) x : \frac{3}{5} = \frac{-5}{2}
9) \frac{3}{4} \left( \frac{1}{4} + x \right) = \frac{-5}{6}

Bài 2. Tìm x:

1) \frac{3}{4} + \frac{1}{4} - x = \frac{-5}{6}
2) 3 \frac{1}{2} - \frac{1}{2} x = \frac{-2}{3}
3) x : \frac{1}{2} + \frac{3}{2} = \frac{5}{4}
4) \frac{5}{8} + \frac{3}{8} : x = \frac{1}{2}
5) \frac{3}{2} x - \frac{1}{4} = \frac{4}{7}
6) \frac{1}{3} + \frac{1}{2} : x = \frac{1}{5}
```

Đây là các phương trình từ ảnh. Bạn có thể sử dụng các bước giải phương trình phân số để tìm giá trị của \( x \).

Answer 1

bài 1:

\(1)x+\frac34=\frac43\Rightarrow x=\frac43-\frac34=\frac{7}{12}\)

\(2)x-\frac35=\frac{4}{15}\Rightarrow x=\frac{4}{15}+\frac35=\frac{13}{15}\)

\(3)-x-\frac{2}{15}=\frac{7}{10}\Rightarrow x=-\frac{2}{15}-\frac{7}{10}=-\frac56\)

\(4)\frac79-x=\frac{1}{12}\Rightarrow x=\frac79-\frac{1}{12}=\frac{25}{36}\)

\(5)\frac34x=\frac{-5}{6}\Rightarrow x=-\frac56:\frac34=-\frac56\cdot\frac43=-\frac{10}{9}\)

\(6)\left(x+\frac23\right)\cdot\frac45=-\frac{8}{15}\Rightarrow x+\frac23=-\frac{8}{15}:\frac45\)

\(x+\frac23=-\frac{8}{15}\cdot\frac54=-\frac23\)

\(x=-\frac23-\frac23=-\frac43\)

\(7)\frac67:x=-\frac{8}{21}\Rightarrow x=\frac67:\left(-\frac{8}{21}\right)\)

\(x=\frac67\cdot\left(-\frac{21}{8}\right)=-\frac94\)

\(8)x:\frac35=-\frac52\Rightarrow x=-\frac52\cdot\frac35=-\frac32\)

\(9)\frac34:\left(\frac14+x\right)=-\frac56\Rightarrow\frac14+x=\frac34:\left(-\frac56\right)\)

\(\frac14+x=\frac34\cdot\left(-\frac65\right)=-\frac{9}{10}\)

\(\Rightarrow x=-\frac{9}{10}-\frac14=-\frac{23}{20}\)

bài 2:

\(1)\frac34+\frac14x=-\frac56\Rightarrow\frac14x=-\frac56-\frac34\)

\(\frac14x=-\frac{19}{12}\Rightarrow x=-\frac{19}{12}:\frac14\)

\(x=-\frac{19}{12}\cdot4=-\frac{19}{3}\)

\(2)3\frac12-\frac12x=-\frac23\Rightarrow\frac72-\frac12x=-\frac23\)

\(\frac12x=\frac72-\left(-\frac23\right)=\frac{25}{6}\)

\(x=\frac{25}{6}:\frac12=\frac{25}{6}\cdot2=\frac{25}{3}\)

\(3)x:\frac12+\frac32=\frac54\Rightarrow x\cdot2=\frac54-\frac32\)

\(x\cdot2=-\frac14\Rightarrow x=-\frac14:2=-\frac14\cdot\frac12=-\frac18\)

\(4)\frac58-\frac38:x=\frac12\Rightarrow\frac38\cdot\frac{1}{x}=\frac58-\frac12\)

\(\frac{3}{8x}=\frac18\Rightarrow24=8x\Rightarrow x=3\)

\(5)\frac32x-\frac14=\frac47\Rightarrow\frac32x=\frac47+\frac14\)

\(\frac32x=\frac{23}{28}\Rightarrow x=\frac{23}{28}:\frac32=\frac{23}{28}\cdot\frac23=\frac{23}{42}\)

\(6)\frac13+\frac12:x=\frac15\Rightarrow\frac12\cdot\frac{1}{x}=\frac15-\frac13\)

\(\frac{1}{2x}=-\frac{2}{15}\Longrightarrow4x=-15\Rightarrow x=-\frac{15}{4}\)