B1.Tìm x, biết: a,34/5:8/5=0,25:x b,2x+3/24=3x-1/32 c,13x-2/2x+5=76/17 B2. Cho tỉ lệ thức a/b=c/d . Chứng minh: a, a/a+b=c/c+d b, a-b/c-d=a+c/b+d
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a) \(3\dfrac{4}{5}:\dfrac{8}{5}=0,25:x\)
\(\Rightarrow\dfrac{19}{5}.\dfrac{5}{8}=\dfrac{x}{4}\)
\(\Rightarrow\dfrac{x}{4}=2\Rightarrow x=8\)
b) \(2x+\dfrac{3}{24}=3x-\dfrac{1}{32}\)
\(\Rightarrow x=\dfrac{1}{8}+\dfrac{1}{32}=\dfrac{5}{32}\)
c) \(\dfrac{13x-2}{2x+5}=\dfrac{76}{17}\)
\(\Rightarrow221x-34=152x+380\)
\(\Rightarrow69x=414\Rightarrow x=6\)
a) \(\dfrac{2x+3}{24}=\dfrac{3x-1}{32}\)
\(\Rightarrow32\left(2x+3\right)=24\left(3x-1\right)\)
\(\Rightarrow64x+96=72x-24\)
\(\Rightarrow8x=120\Rightarrow x=15\)
b) \(\dfrac{13x-2}{2x+5}=\dfrac{76}{17}\)
\(\Rightarrow17\left(13x-2\right)=76\left(2x+5\right)\)
\(\Rightarrow221x-34=152x+380\)
\(\Rightarrow69x=414\Rightarrow x=6\)
a) \(\dfrac{2x+3}{24}=\dfrac{3x-1}{32}\\ =>32\left(2x+3\right)=24\left(3x-1\right)\\ =>64x+96=72x-24\\ =>72x-64x=24+96\\ =>8x=120\\ =>x=120:8\\ =>x=15\)
b) \(\dfrac{13x-2}{2x+5}=\dfrac{76}{17}\\=>76\left(2x+5\right)=17\left(13x-2\right)\\ =>152x+380=221x-34\\ =>221x-152x=34+380\\ =>69x=414\\ =>x=414:69\\ =>x=6\)
a.
\(\dfrac{2x+3}{24}=\dfrac{3x-1}{32}\)
\(\Leftrightarrow\dfrac{4\left(2x+3\right)}{4.24}=\dfrac{3\left(3x-1\right)}{32.3}\)
\(\Leftrightarrow\dfrac{8x+12}{96}=\dfrac{9x-3}{96}\)
\(\Leftrightarrow8x+12=9x-3\)
\(\Leftrightarrow9x-8x=12+3\)
\(\Leftrightarrow x=15\)
b.
ĐKXĐ: \(x\ne-\dfrac{5}{2}\)
\(\dfrac{13x-2}{2x+5}=\dfrac{76}{17}\)
\(\Leftrightarrow\dfrac{17\left(13x-2\right)}{17\left(2x+5\right)}=\dfrac{76\left(2x+5\right)}{17\left(2x+5\right)}\)
\(\Rightarrow17\left(13x-2\right)=76\left(2x+5\right)\)
\(\Leftrightarrow221x-34=152x+380\)
\(\Leftrightarrow69x=414\)
\(\Leftrightarrow x=6\)
\(a,\frac{34}{5}:\frac{8}{5}=0,25:x\)
\(\frac{17}{4}=\frac{1}{4}:x\)
\(x=\frac{1}{4}:\frac{17}{4}\)
\(x=\frac{1}{17}\)
\(b,2x+\frac{3}{24}=3x-\frac{1}{32}\)
\(2x-3x=\frac{-1}{32}-\frac{1}{8}\)
\(-x=\frac{-5}{32}\)
\(x=\frac{5}{32}\)
\(13x-\frac{2}{2}x+5=\frac{76}{17}\)
\(12x=\frac{-9}{17}\)
\(x=\frac{-3}{68}\)
a,\(\frac{34}{5}\div\frac{8}{5}=0,25\div x\)
\(\frac{17}{4}=0,25\div x\)
\(x=17\)
b,\(2x+\frac{3}{24}=3x-\frac{1}{32}\)
\(\Leftrightarrow2x-3x=-\frac{1}{32}-\frac{3}{24}\)
\(\Leftrightarrow2x-3x=-\frac{5}{32}\)
\(\Leftrightarrow-x=-\frac{5}{32}\)
\(\Leftrightarrow x=\frac{5}{32}\)