Let be and Mn intersect at point O and MP intersect at point P parallel to AD.

Then s = sampd+s △ MNP

△MNP is all equal to△△△ BEA (corner edge)

There is s △ MNP = s△ BEA = 1/2.

*x*2=x

In △ABE, AE = X.

Then be = √ (4+x 2)

△BOM is similar to△△△ BAE (angle).

There is bo: ba = BM: be

And bo = 1/2.

* Yes

So BM = 1/2.

*BE^2/AB

= 1/4

*x^2

+

1

So am = ab-BM = 1- 1/4.

*x^2

So s =-0.25 x 2+ 1.

+x

The binomial above has a maximum when x=2.