MathDB
<B =? , (ABCD)=(a+b)h/2

Source: 1998 Swedish Mathematical Competition p4

April 2, 2021
geometryanglesarea

Problem Statement

ABCDABCD is a quadrilateral with A=90o\angle A = 90o, AD=aAD = a, BC=bBC = b, AB=hAB = h, and area (a+b)h2\frac{(a+b)h}{2}. What can we say about B\angle B?