\(\left(x+8\right)\left(x+6\right)-x^2=104\)
\(\Rightarrow x^2+14x+48-x^2=104\)
\(\Rightarrow14x=56\Rightarrow x=4\)
\(\Rightarrow x^2+14x+48-x^2=104\\ \Rightarrow14x=56\\ \Rightarrow x=4\)
\(\left(x+8\right)\left(x+6\right)-x^2=104\)
\(\Leftrightarrow14x=56\)
hay x=4