Question 525873


{{{(x+9)^2=20}}} Start with the given equation.



{{{x+9=""+-sqrt(20)}}} Take the square root of both sides.



{{{x+9=sqrt(20)}}} or {{{x+9=-sqrt(20)}}} Break up the "plus/minus" to form two equations.



{{{x+9=2*sqrt(5)}}} or {{{x+9=-2*sqrt(5)}}}  Simplify the square root.



{{{x=-9+2*sqrt(5)}}} or {{{x=-9-2*sqrt(5)}}} Subtract {{{9}}} from both sides.



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Answer:



So the exact solutions are {{{x=-9+2*sqrt(5)}}} or {{{x=-9-2*sqrt(5)}}}.



which approximate to {{{x=-4.528}}} or {{{x=-13.472}}}



Note: use a calculator to find the approximations