Question 892730
For a rectangle,
{{{A=L*W}}}
In this case,
{{{L*W=475}}}
and
{{{L=3+W}}}
Substituting,
{{{(3+W)W=475}}}
{{{W^2+3W=475}}}
{{{W^2+3W+(9/4)=475+9/4}}}
{{{(W+3/2)^2=1900/4+9/4}}}
{{{(W+3/2)^2=1909/4}}}
{{{W+3/2=0 +- sqrt(1909)/2}}}
{{{W=-3/2 +- sqrt(1909)/2}}}
Only the positive solution makes sense in this problem.
{{{highlight(W=sqrt(1909)/2-3/2)}}}
Then,
{{{L=3+sqrt(1909)/2-3/2}}}
{{{highlight(L=sqrt(1909)/2+3/2)}}}