The images of 1 and linear function y=4/3X+4 intersect the X axis and the Y axis at point AB, respectively.

X=0 Y=4

Y=0 X=-3

A(-3，0) B(0，4)

2. The straight line AB rotates 90 clockwise around the O-point, and intersects with the X-axis and the Y-axis at the C and D points respectively.

C(4，0) D(0，3)

The analytical formula of linear CD is Y=-3/4X+3.

4/3X+4=-3/4X+3

4/3X+3/4X=- 1

25/ 12X=- 1

X=- 12/25

The abscissa of point E is -25/ 12.

So the area of △BDE =25/24.

3. There is a moving point P on the X axis, so △CDP is the coordinate of an isosceles triangle and the moving point P..

(-4,0)(- 1,0)(9,0)(7/8,0)