Câu hỏi của Nguyễn Thị Mai Phương

Question

2. Tìm x, biết

a) $\dfrac{-1}{4}$-$\dfrac{3}{4}$:x =$\dfrac{-11}{36}$

b) $70$: $\dfrac{4x+720}{x}$=$\dfrac{1}{2}$

Giúp mình với

Đức Hiếu · Accepted Answer

a, $-\dfrac{1}{4}-\dfrac{3}{4}:x=-\dfrac{11}{36}$

$\Rightarrow\dfrac{3}{4}:x=-\dfrac{1}{4}-\left(-\dfrac{11}{36}\right)=\dfrac{1}{18}$

$\Rightarrow x=\dfrac{3}{4}:\dfrac{1}{18}=\dfrac{27}{2}$

b, $70:\dfrac{4x+720}{x}=\dfrac{1}{2}$

$\Rightarrow\dfrac{4x+720}{x}=140$

$\Rightarrow4x+720=140x\Rightarrow140x-4x=720$

$\Rightarrow136x=720\Rightarrow x=\dfrac{90}{17}$

Chúc bạn học tốt!!!Câu trả lời: a, $-\dfrac{1}{4}-\dfrac{3}{4}:x=-\dfrac{11}{36}$

$\Rightarrow\dfrac{3}{4}:x=-\dfrac{1}{4}-\left(-\dfrac{11}{36}\right)=\dfrac{1}{18}$

$\Rightarrow x=\dfrac{3}{4}:\dfrac{1}{18}=\dfrac{27}{2}$

b, $70:\dfrac{4x+720}{x}=\dfrac{1}{2}$

$\Rightarrow\dfrac{4x+720}{x}=140$

$\Rightarrow4x+720=140x\Rightarrow140x-4x=720$

$\Rightarrow136x=720\Rightarrow x=\dfrac{90}{17}$

Chúc bạn học tốt!!!

Quang Duy · Answer

a)$\dfrac{-1}{4}-\dfrac{3}{4}:x=\dfrac{-11}{36}$

$\dfrac{3}{4}:x=\dfrac{-1}{4}-\left(\dfrac{-11}{36}\right)=\dfrac{1}{18}$

$\Rightarrow x=\dfrac{3}{4}:\dfrac{1}{18}=\dfrac{27}{2}$

b)$70:\dfrac{4x+720}{x}=\dfrac{1}{2}$

$\dfrac{4x+720}{x}=70:\dfrac{1}{2}=140$

$\Rightarrow4x+720=140x$

$\Rightarrow140x-4x=720$

$\Rightarrow136x=720$

$\Rightarrow x=\dfrac{90}{17}$Câu trả lời: a)$\dfrac{-1}{4}-\dfrac{3}{4}:x=\dfrac{-11}{36}$

$\dfrac{3}{4}:x=\dfrac{-1}{4}-\left(\dfrac{-11}{36}\right)=\dfrac{1}{18}$

$\Rightarrow x=\dfrac{3}{4}:\dfrac{1}{18}=\dfrac{27}{2}$

b)$70:\dfrac{4x+720}{x}=\dfrac{1}{2}$

$\dfrac{4x+720}{x}=70:\dfrac{1}{2}=140$

$\Rightarrow4x+720=140x$

$\Rightarrow140x-4x=720$

$\Rightarrow136x=720$

$\Rightarrow x=\dfrac{90}{17}$

Bài 3: Nhân, chia số hữu tỉ