\(\left(\frac{3x}{7}+1\right):\left(-4\right)=\frac{-1}{28}\)
Giúp mik với
Tìm x, biết :
\(\frac{7}{\left(x+3\right)\left(x+10\right)}+\frac{3}{\left(x-4\right)\left(x-7\right)}+\frac{6}{\left(x-7\right)\left(x-13\right)}\)
\(+\frac{15}{\left(x-13\right)\left(x-28\right)}-\frac{1}{x-28}=\frac{-1}{20}\)
giúp mình với các bạn !!!!!!!!!!!!
\(\left(\frac{3x}{7}+1\right)=\frac{-1}{28}.\left(-4\right)\)
\(\left(\frac{3x}{7}+1\right)=\frac{-1}{28}.\left(-4\right)\)
\(\left(\frac{3x}{7}+1\right)=\frac{1}{7}\)
\(\frac{3x}{7}=\frac{1}{7}-1\)
\(\frac{3x}{7}=\frac{-6}{7}\)
=> 3x = -6
=> x = -6 : 3
=> x = -2
Vậy x = -2
\(\left(\frac{3x}{7}+1\right)=\frac{-1}{28}.\left(-4\right)\)
\(\left(\frac{3x}{7}+1\right)=\frac{1}{7}\)
\(\frac{3x}{7}=\frac{1}{7}-1=\frac{-6}{7}\)
\(3x=-6\)
\(=>x=\left(-6\right):3=-2\)
\(\left(\frac{3x}{7}+1\right)=\frac{-1}{28}.\left(-4\right)\)
\(\Rightarrow\left(\frac{3x+7}{7}\right)=\frac{1}{7}\)
=> 3x+7=1
=>3x=-6
=>x=-2
Bài 1:tính giá trị biểu thức sau:
\(B=\left(1-\frac{1}{21}\right).\left(1-\frac{1}{28}\right).\left(1-\frac{1}{36}\right)...\left(1-\frac{1}{1326}\right)\)
Bài 2 tìm x biết
\(a,1\frac{1}{30}:\left(24\frac{1}{6}-24\frac{1}{5}\right)-\frac{1\frac{1}{2}-\frac{3}{4}}{4x-\frac{1}{2}}=\left(-1\frac{1}{15}\right):\left(8\frac{1}{5}-8\frac{1}{3}\right)\)
\(b,\left|3x-\frac{2}{5}\right|=\frac{1}{35}+\left|\frac{-3}{7}\right|\)
\(c,-3\frac{1}{2}-\left(2x+\frac{1}{2}\right):\left(-\frac{3}{7}\right)=0\)
\(d,\left(x-4\right).\left(x+2\right)\le0\)với x thuộc z
giúp mk với
\(\left(\frac{3x}{7}+1\right)\div\left(-4\right)=\frac{-1}{28}\)
\(\left(\frac{3x}{7}+1\right)\div\left(-4\right)=\frac{-1}{28}\)
\(\frac{3x}{7}+1=\frac{-1}{28}\times\left(-4\right)\)
\(\frac{3x}{7}+1=\frac{1}{7}\)
\(\frac{3x}{7}=\frac{1}{7}-1\)
\(\frac{3x}{7}=\frac{-6}{7}\)
\(3x=\frac{-6}{7}\times7\)
\(3x=-6\)
\(x=-2\)
Vậy x = -2
tớ ko bít đúng hay sai đâu nha
\(\Leftrightarrow\)\(-\frac{1}{28}\cdot\left(-4\right)\)=\(\frac{3x}{7}+1\)
\(\Leftrightarrow\frac{1}{7}=\frac{3x}{7}+1\)
\(\Leftrightarrow\frac{1}{7}-1=3x:7\)
\(\Leftrightarrow3x:7=-\frac{6}{7}\)
\(\Leftrightarrow3x=\frac{-6}{7}.7\)
\(\Leftrightarrow x=-6:3\)
\(\Leftrightarrow x=-2\)
Tìm x :\(\left(\frac{3x}{7}+1\right):\left(-4\right)=-\frac{1}{28}\)
\(\left(\frac{3x}{7}+1\right):\left(-4\right)=\frac{-1}{28}\)
\(\Leftrightarrow\frac{3x+7}{7}.\frac{1}{-4}=\frac{-1}{28}\)
\(\Leftrightarrow-\frac{3x+7}{28}=\frac{-1}{28}\)
\(\Leftrightarrow-\left(3x+7\right)=-1\)
\(\Leftrightarrow3x+7=1\)\(\Leftrightarrow3x=-6\)
\(\Leftrightarrow x=-2\)
\(Q=\left(\frac{2}{25}-1,008\right):\frac{4}{7}:\left[\left(3\frac{1}{4}-6\frac{5}{9}\right).2\frac{2}{7}\right]\)
Những ai giỏi giúp mik với nhé
\(Q=\left(\frac{2}{25}-1,008\right):\frac{4}{7}:\left[\left(3\frac{1}{4}-6\frac{5}{9}\right)\cdot2\frac{2}{7}\right]\)
\(Q=\left(\frac{2}{25}-\frac{126}{125}\right):\frac{4}{7}:\frac{-68}{9}\)
\(Q=\frac{-116}{125}:\frac{4}{7}:\frac{-68}{9}\)
\(Q=\frac{-203}{125}:\frac{-68}{9}\)
\(Q=\frac{1827}{8500}\)
\(\frac{3}{\left(x-4\right)\left(x-7\right)}+\frac{6}{\left(2-7\right)\left(x-13\right)}+\frac{15}{\left(x-13\right)\left(x-28\right)}-\frac{1}{x-28}=-\frac{1}{20}\)
\(\frac{3}{\left(x-4\right)\left(x-7\right)}+\frac{6}{\left(2-7\right)\left(x-13\right)}+\frac{15}{\left(x-13\right)\left(x-28\right)}-\frac{1}{x-28}=-\frac{1}{20}\)
ghi sai để nên mik ko giải dc
\(\frac{3}{\left(x-4\right)\left(x-7\right)}+\frac{6}{\left(2-7\right)\left(x-13\right)}+\frac{15}{\left(x-13\right)\left(x-28\right)}-\frac{1}{x-28}=-\frac{1}{20}\)