For rectangle
l=3.07m
b=2.24m
so longest side that can be drawn is diagonal of rectangular board
=squareroot l^2+b^2
=squareroot3.07^2+2.24^2
=squareroot9.4249+5.0176
=squareroot14.4425
=3.80
So longest line that can be drawn in rectangular board is 3.80m