Question 1130353
THREE RECTANGULAR SECTIONS.
Dimensions x and y for the entire garden


Let y be the length of the house to use for one whole side of the garden.
If the two divider fence parts are parallel to the x dimension, then:

{{{x+x+x+x+y=56}}}

{{{4x+y=56}}}


Formula for garden area, A
{{{A=xy}}}
{{{highlight_green(A=x(56-4x))}}}

You can use this formula to find the x for the maximum A, and use result to find y.   (Maximum occurs in exact middle of the two zeros of A).