The given quadrilateral ABCD is an isosceles trapezoid. Which choice is NOT true about ABCD?
A) 2x + 10 = 4x - 30
B) angle A+ angle B+ angle C+ angle D=180°
C) angle A+ angle B+ angle C+ angle D=360°
D) AB = CD

Solve for angle DAB.
A) 50°
B) 20°
C) 30°
D) 65°