Question 872940
x and y dimensions;
xy=4200 and p for perimeter is p=2x+2y.


You only have enough information to make {{{highlight(p=2(4200/y)+2y)}}} or {{{highlight(p=2x+2(4200/x))}}}; or to solve each of these for y in terms of p or to solve x in terms of p.  You need to know which variables are known and which variables are unknown.


Either py=8400+2y^2, {{{highlight(2y^2-py+8400=0)}}}
OR
px=2x^2+8400, {{{highlight(2x^2-px+8400=0)}}}