It is known that the waist of a right angle trapezoid is 10cm, the angle between the waist and the bottom is 30 degrees, and the length of the upper bottom is 3cm

It is known that the waist of a right angle trapezoid is 10cm, the angle between the waist and the bottom is 30 degrees, and the length of the upper bottom is 3cm

∵ the waist of the right angled trapezoid is 10cm, and the angle between the waist and the bottom is 30 degrees. Through the point connecting the waist and the upper bottom, make the vertical line of the lower bottom,
The length of the vertical line = the length of the other waist = 10 △ 2 = 5 (?)
The length of the vertical line perpendicular to the vertex with an angle of 30 degrees = √ 10 & sup2; - 5 & sup2; = 5 √ 3 (· cm), and the length of the bottom = (5 √ 3 + 3) · cm
The area of this trapezoid = (3 + 5 √ 3 + 3) × 5 △ 2 = (30 + 25 √ 3) / 2 ( & sup2;)
A: the other waist of trapezoid is 5cm, and the area of trapezoid is (30 + 25 √ 3) / 2cm & sup2