On the photograph of Problem 27.12, the image d of a third point D appears.Its elevation is hD = 1195 ft, and its photo coordinates are xd = 56.86 mm and yd = 63.12 mm. Calculate the area, in acres, of triangle ABD.
Problem 27.12:
Determine the horizontal distance between two points A and B whose elevations above datum are hA = 1560 ft and hB = 1425 ft, and whose images a and b on a vertical photograph have photo coordinates xa = 2.95 in., ya = 2.32 in.,xb = -1.64 in., and yb = -2.66 in. The camera focal length was 152.4 mm and the flying height above datum 7500 ft.