\(\left(x-3\right).\left(x-5\right)=7\)
\(\Rightarrow x^2-5x-3x+15=7\)
\(\Rightarrow x^2-8x+8=0\)
\(\Rightarrow\orbr{\begin{cases}x=4+2\sqrt{2}\\x=4-2\sqrt{2}\end{cases}}\)
(x-3)x(x-5)=7
x-3 =7
x=7+3
x=10
Hoặc:x-5=7
x=7+5
x=12
Vậy x bằng 10 hoặc x bằng 12