\(\left(x+3\right)^2-\left(x-4\right)\left(x+8\right)=1\)
\(\left(x^2+6x+9\right)-\left(x^2+8x-4x-32\right)=1\)
\(x^2+6x+9-x^2-8x+4x+32=1\)
\(2x+41=1\)
\(\Rightarrow x=\dfrac{40}{2}=20\)
\(\left(x+3\right)^2-\left(x-4\right)\left(x+8\right)=1\)
\(\Leftrightarrow x^2+6x+9-x^2+8x-4x-32=1\)
\(\Leftrightarrow x^2+6x+9-\left(x^2+4x-32\right)=1\)
\(\Leftrightarrow x^2+6x+9-x^2-4x+32=1\)
\(\Leftrightarrow2x+41=1\)
\(\Leftrightarrow2x=-40\Leftrightarrow x=-20\)
\(\left(x+3\right)^2-\left(x-4\right)\left(x+8\right)=1\)
\(\left(x^2+6x+9\right)-\left(x^2+8x-4x-32\right)=1\)
\(x^2+6x+9-x^2-8x+4x+32=1\)
\(2x+41=1\)
\(x=\dfrac{-40}{2}=-20\)