Question 1085021
Dimensions:
3w, w, 2w


Total Surface Area:
{{{2*3w*w+2*w*2w+2*3w*2w=198}}}
{{{6w^2+4w^2+12w^2=198}}}
{{{22w^2=198}}}
{{{w^2=9}}}
{{{highlight(w=3)}}}



Now, dimensions are known:
9, 3, 6


The diagonal?
{{{sqrt(9^2+3^2+6^2)}}}
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