Question 281420
Let x = width
Then 2x + 6 = length

We need 2 widths, and 2 lengths to equal 288.

{{{2x + 2(2x + 6) = 288}}}
{{{2x + 4x + 12 = 288}}}
{{{6x = 276}}}
{{{x = highlight(46)}}} width
{{{2x + 6 = highlight(98)}}} length

Prove:  46+98+46+98=288.