5. Let 0 < a < b < 2a. We will consider the curve ry = 1 on [a, b]. We now sketch a tangent line at any point (x, y)

on this curve with x-coordinate in [a, b]. Then we will have a trapezoid and its four sides are on this tangent line, x-axis, x = a and x = b. Find the point (x, y) such that the area of the trapezoid is the largest.