Question 851045
{{{9k^2+21=25}}}



{{{9k^2=25-21}}}



{{{9k^2=4}}}



{{{k^2=4/9}}}



{{{k=""+-sqrt(4/9)}}}



{{{k=sqrt(4/9)}}} or {{{k=-sqrt(4/9)}}}



{{{k=2/3}}} or {{{k=-2/3}}}



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The two solutions are {{{k=2/3}}} or {{{k=-2/3}}}