Question

N trapezoid ABCD, find m∠A if m∠B= 25°, m∠C = 155° and m∠ D= 117°. A) 25° B) 63° C) 73° D) 92°

Answer 1

Sum of the angles of the trapezoid (quadrilateral) add up to 360°, so based on available information 
mâ A + mâ B + mâ C + mâ D = 360° relates to mâ A + 25° + 155°
+ 117°.=360°
So,  mâ A = 360° - (25°+155°+117°)
mâ A = 360° - 297°
mâ A = 63°