Verified Answer :

Exvited

\(A = \frac{1}{2} \times ( \frac{314}{100} ) w^{2} +2lw \\ \\ 2lw + \frac{157}{100} w^{2} = a \\ \\ 2lw = \frac{-157}{100} w^{2} + a \\ \\ l = \frac{-157 w^{2} + 100a}{200w} \\ \\ Answer: l = -157w^{2} + 100a/200w\)

TSO

\(A=\frac{1}{2}*(\frac{314}{100})w^2+2lw\\\\A = 1.57w^2 + 2lw\\\\A = w(1.57w +2l)\\\\\frac{A}{w} =1.57w + 2l\\\\2l = \frac{A}{w} - 1.57w\\\\l = \frac{A}{2w}-\frac{1.57w}{2}\\\\\boxed{\bf{L= -0.785w + \frac{A}{2w}}}\)