As shown in the figure, ab ∥ CD, ∠ ACB = 90 °, e is the midpoint of AB, CE = CD, de and AC intersect at F.; De is perpendicular to AC, and angle ACD = angle As shown in the figure, it is known that AB / / CD, ∠ ACB = 90 °, e is the midpoint of AB, CE = CD, de and AC intersect at F, and the verification is as follows:

As shown in the figure, ab ∥ CD, ∠ ACB = 90 °, e is the midpoint of AB, CE = CD, de and AC intersect at F.; De is perpendicular to AC, and angle ACD = angle As shown in the figure, it is known that AB / / CD, ∠ ACB = 90 °, e is the midpoint of AB, CE = CD, de and AC intersect at F, and the verification is as follows:

prove:
Because ∠ ACB = 90, e is the midpoint of ab
So CE = AB / 2 = AE, (the middle line on the hypotenuse of a right triangle equals half of the hypotenuse)
Therefore, a = ace
Because ab ‖ CD
So ∠ a = ∠ ACD,
Therefore, ACD = ace
And because CE = CD
So de ⊥ AC