Solution: obtained by (1), AP/AC=AE/AB=DE/BC.
That is x/8=AE/ 10=DE/6.
AE=5x/4 PE=3x/4。
And the perimeter of the quadrilateral PECB is y, that is
PE+EC+CB+BP=y
Then 3x/4+(8-5x/4)+6+(10-x) = y.
Simplify and acquire
y=24-3x/2
Ok, the image is a straight line. If you stop asking me,