Các bước giải:
a/(x-3)(x-1)-3(x-3)=0
⇒(x-3)(x-1-3)=0
⇒(x-3)(x-4)=0
⇒\(\left[ \begin{array}{l}x-3=0\\x-4=0\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=3\\x=4\end{array} \right.\)
Vậy x=3 hoặc x=4
b/(2x+5)²-(x-9)²=0
⇒(2x+5-x+9)(2x+5+x-9)=0
⇒(x+14)(3x-4)=0
⇒\(\left[ \begin{array}{l}x+14=0\\3x-4=0\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=-14\\x=4/3\end{array} \right.\)
Vậy x=-14 hoặc x=4/3
c/(6x+3)-(2x-5)(2x+1)=0
⇒3(2x+1)-(2x-5)(2x+1)=0
⇒(2x+1)(3-2x+5)=0
⇒(2x+1)(8-2x)=0
⇒\(\left[ \begin{array}{l}2x+1=0\\8-2x=0\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=-1/2\\x=4\end{array} \right.\)
Vậy x=-1/2 hoặc x=4
d/(3x-1)-16=0
⇒(3x-1)-4²=0
⇒(3x-1-4)(3x-1+4)=0
⇒(3x-5)(3x+3)=0
⇒\(\left[ \begin{array}{l}3x-5=0\\3x+3=0\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=5/3\\x=-1\end{array} \right.\)
Vậy x=5/3 hoặc x=-1
