\(a,\Leftrightarrow4x=10\)
\(\Leftrightarrow x=\dfrac{5}{2}\)
Vậy \(S=\left\{\dfrac{5}{2}\right\}\)
\(b,\Leftrightarrow-3x+x=9-7\)
\(\Leftrightarrow-2x=2\)
\(\Leftrightarrow x=-1\)
Vậy \(S=\left\{-1\right\}\)
\(c,\Leftrightarrow2x-3+5x=4x+12\)
\(\Leftrightarrow2x+5x-4x=12+3\)
\(\Leftrightarrow3x=15\)
\(\Leftrightarrow x=5\)
Vậy \(S=\left\{5\right\}\)
\(d,\Leftrightarrow5-6+x=12-8x\)
\(\Leftrightarrow8x+x=12-5+6\)
\(\Leftrightarrow9x=13\)
\(\Leftrightarrow x=\dfrac{13}{9}\)
Vậy \(S=\left\{\dfrac{13}{9}\right\}\)
\(e,\Leftrightarrow4x+12=-7x+17\)
\(\Leftrightarrow4x+7x=17-12\)
\(\Leftrightarrow11x=5\)
\(\Leftrightarrow x=\dfrac{5}{11}\)
Vậy \(S=\left\{\dfrac{5}{11}\right\}\)
Các sau bạn cũng làm tương tự, nhân các ngoặc ra dạng x hoặc số rồi áp dụng quy tắc chuyển vế.
này là bài tập e không biết làm thôi ad đừng xóa bài của e;(
\(a,4x-10=0\\ \Rightarrow x=\dfrac{5}{2}\\ b,7-3x=9-x\\ \Rightarrow9-x-7+3x=0\\ \Rightarrow2x+2=0\\ \Rightarrow x=-1\\ c,2x-\left(3-5x\right)=4\left(x+3\right)\\ \Rightarrow2x-3+5x=4x+12\\ \Rightarrow7x-3-4x-12=0\\ \Rightarrow3x-15=0\\ \Rightarrow x=5\\ d,5-\left(6-x\right)=4\left(3-2x\right)\\ \Rightarrow5-6+x=12-8x\\ \Rightarrow x-1-12+8x=0\\ \Rightarrow9x-13=0\\ \Rightarrow x=\dfrac{13}{9}\\ e,4\left(x+3\right)=-7x+17\\ \Rightarrow4x+12+7x-17=0\\ \Rightarrow11x-5=0\\ \Rightarrow x=\dfrac{5}{11}\)
\(f,5\left(x-3\right)-4=2\left(x-1\right)+7\\ \Rightarrow5x-15-4=2x-2+7\\ \Rightarrow5x-19=2x+5\\ \Rightarrow5x-19-2x-5=0\\ \Rightarrow3x-24=0\\ \Rightarrow x=8\\ g,5\left(x-3\right)-4=2\left(x-1\right)+7\\ \Rightarrow5x-15-4=2x-2+7\\ \Rightarrow5x-19=2x+5\\ \Rightarrow5x-19-2x-5=0\\ \Rightarrow3x-24=0\\ \Rightarrow x=8\)
\(h,4\left(3x-2\right)-3\left(x-4\right)=7x+20\\ \Rightarrow12x-8-3x+12=7x+20\\ \Rightarrow9x+4=7x+20\\ \Rightarrow9x+4-7x-20=0\\ \Rightarrow2x-16=0\\ \Rightarrow x=8\)
