Câu 1:
\(a)5\left(2x+3\right)-4\left(x+1\right)-6=0.\\ \Leftrightarrow10x+15-4x-4-6=0.\\ \Leftrightarrow6x+5=0.\\ \Leftrightarrow x=\dfrac{-5}{6}.\)
\(b)\left(x+2\right)^2-x\left(x-4\right)+7=0.\\x^2+4x+4-x^2+4x+7=0.\\ \Leftrightarrow8x+11=0.\\ \Leftrightarrow x=\dfrac{-11}{8}. \)
Câu 2:
\(a)\dfrac{3x-1}{5}-\dfrac{x+2}{4}=\dfrac{7}{6}.\\ \Leftrightarrow\dfrac{12x-4-5x-10}{20}=\dfrac{7}{6}.\\ \Leftrightarrow\dfrac{7x-14}{20}=\dfrac{7}{6}.\\ \Rightarrow42x-84=140.\\ \Leftrightarrow x=\dfrac{16}{3}.\)
\(b)\dfrac{5x+2}{3}-\dfrac{x-1}{4}=\dfrac{x+2}{5}.\\ \Leftrightarrow\dfrac{100x+40-15x+15-12x-24}{60}=0.\\ \Rightarrow73x=-31.\Leftrightarrow x=\dfrac{-31}{73}.\)
