\(\left(x+5\right)^2-3=13\)
\(\left(x+5\right)^2\) \(=13+3\)
\(\left(x+5\right)^2\) \(=16\)
\(\Leftrightarrow x+5\) \(=\sqrt{16}\)
\(x+5\) \(=4\)
\(x\) \(=4-5\)
\(x\) \(=-1\)
\(\left(x+5\right)^2-3=13\\ \left(x+5\right)^2=13+3\\ \left(x+5\right)^2=16\\ TH1:\\ \left(x+5\right)^2=4^2\\ x+5=4\\ x=4-5\\ x=-1\\ TH2:\left(x+5\right)^2=\left(-4\right)^2\\ \\ x+5=-4\\ x=-4-5\\ x=-9\)