It is known that: as shown in the figure, in the trapezoidal ABCD, ad ‖ BC, ad = 24cm, BC = 30cm, point P moves from point a to D at a speed of 1cm / s, and stops at point D. point Q moves from point C to B at a speed of 2cm / S, and stops at point B. the straight line PQ cuts the trapezoid into two quadrangles?

It is known that: as shown in the figure, in the trapezoidal ABCD, ad ‖ BC, ad = 24cm, BC = 30cm, point P moves from point a to D at a speed of 1cm / s, and stops at point D. point Q moves from point C to B at a speed of 2cm / S, and stops at point B. the straight line PQ cuts the trapezoid into two quadrangles?

Let P and Q start at the same time. After T seconds, the quadrilateral pdcq or quadrilateral apqb is a parallelogram. According to the known results, AP = t, PD = 24-t, CQ = 2T, BQ = 30-2t. (1) if the quadrilateral pdcq is a parallelogram, then PD = CQ, ∧ 24-t = 2T, ∧ t = 8, ∧ after 8 seconds, the quadrilateral pdcq is a parallelogram; (2) if the quadrilateral apqb is a parallelogram, then AP = BQ, ∧ t = 30-2t, ∧ t = 10, ∧ after 10 seconds The shape apqb is a parallelogram. Either 10 seconds or 8 seconds after departure is a parallelogram