a:(x+5)(2x-6)=0
=>x+5=0 hoặc 2x-6=0
=>x=-5 hoặc x=3
b: \(\dfrac{x+1}{6}+\dfrac{2x-5}{4}=\dfrac{x-3}{12}\)
=>2x+2+3(2x-5)=x-3
=>2x+2+6x-15=x-3
=>8x-13=x-3
=>7x=10
hay x=10/7
c: \(\dfrac{x-3}{x-2}+\dfrac{3x-2}{x^2-4}=2\)
\(\Leftrightarrow\left(x-3\right)\cdot\left(x+2\right)+3x-2=2x^2-8\)
\(\Leftrightarrow2x^2-8=x^2-x-6+3x-2=x^2+2x-8\)
\(\Leftrightarrow x^2-2x=0\)
=>x(x-2)=0
=>x=0(nhận) hoặc x=2(loại)