(1) Because EF is parallel to BC, all three angles of triangle ABC and triangle AEF are equal. (Parallelism theorem is known) So two triangles are similar. Let's set the length bit L of AG, true X/4=L/3(4 is BC length and 3 is AD length).

Therefore, l = 3x/43/4x (0

(2) (Point P and Point A are on opposite sides of the straight line EF) means that P is below EF. Because the triangle PEF is a right-angled triangle PEF, EF is the hypotenuse. If the line from point P is perpendicular to EF and the focus is H, then the PH value is higher than PEF. Cutting PH=2/ 1EF

When point P is within BCEF, it is. y = XX/4 1/2x & lt； =(3-L) L=3x/4.0