Question 1002018
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x^2 + 6^2 = 12^2

x^2 = 12^2 -6^2

x^2= 108

{{{x= sqrt(108)}}}


{{{x=6sqrt(3)}}}

perimeter = 2 (l+b)

={{{2*(6*(sqrt((3))+6))}}}


= {{{2*6(sqrt(3)+1)}}}

= {{{12*((sqrt(3))+1))}}}