讲解下这个题目---**Example 9** **Problem Description:** As shown in the figure, the analytical expression of line l1 is: y = -3x + 3, and l1 intersects the x-axis at point D. Line l2 passes through points A and B, and lines l1 and l2 intersect at point C. **Figure Description:** * Type: Coordinate plane diagram with two lines. * Coordinate System: X-axis and Y-axis intersecting at the origin O. * Lines: * Line l1: Passes through the y-axis at point (0, 3) and intersects the x-axis at point D. It has a negative slope. * Line l2: Passes through point A and point B. It has a positive slope. * Points: * O: Origin (0,0). * A: Labeled with coordinates (4,0) on the x-axis. * D: Intersection of line l1 and the x-axis. * B: A point on line l2. Its exact coordinates are not labeled, but it is indicated below the x-axis and to the left of A. A horizontal dashed line from B intersects the y-axis at y = 3/2. A vertical dashed line from B appears to intersect the x-axis somewhere between O and D. * C: Intersection point of line l1 and line l2. It is located in the fourth quadrant. * Labels/Annotations: * 'l1' labeling the line with negative slope. * 'l2' labeling the line with positive slope. * 'y' labeling the vertical axis. * 'x' labeling the horizontal axis. * 'O' labeling the origin. * 'D' labeling the x-intercept of l1. * 'A(4,0)' labeling the point A on the x-axis. * 'B' labeling a point on l2. * 'C' labeling the intersection of l1 and l2. * '3' labeled on the y-axis indicating the y-intercept of l1. * '3/2' labeled on the y-axis, associated with a dashed line from point B. **Questions:** (1) Find the coordinates of point D; (2) Find the analytical expression of line l2; (3) Find the area of triangle ADC; (4) On line l2, there is another point P different from point C, such that the area of triangle ADP is equal to the area of triangle ADC. Please directly write the coordinates of point P.