\(a,x^2=16\\ \Rightarrow x^2=4^2\\ \Rightarrow x=4\\ b,x^2=\left(-3\right)^2\\ \Rightarrow x=-3\\ g,\left(x-2\right)^2=16\\ \Rightarrow\left(x-2\right)^2=4^2\\ \Rightarrow x-2=4\\ \Rightarrow x=2\\ h,\left(x+1\right)^2=\left(-3\right)^2\\ \Rightarrow x+1=-3\\ x=-3-1\\ x=-4\\ i,x^2-2x=4\\ \Rightarrow x^2-2x-4=0\\ \Delta'=b'^2-ac=\left(-1\right)^2-1\cdot\left(-4\right)=5\\ \Delta'>0\\ \Rightarrow x_1=\dfrac{-b'+\sqrt{\Delta'}}{a}=1+\sqrt{5}\\ x_2=\dfrac{-b'-\sqrt{\Delta'}}{a}=1-\sqrt{5}\)
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