Question 1157163
You can try to draw the figure and label the parts.
If x is one dimension and y the other dimension of the cardboard, then


{{{system(2(x-4)(y-4)=126,and,xy=143)}}}


Substituting for y and doing the algebra steps:
{{{24-143/x-x=0}}}

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{{{x^2-24x+143=0}}}


{{{highlight_green((x-11)(x-13)=0)}}}

Dimensions of the piece of cardboard,  13 and 11