A rectangular plot of land is represented on a map by the vertices (10,10) , (10,90) , (70.5, 90) , (70.5, 10), where the x and y coordinates are measured in yards. What us the area of the plot of land? A 1560 yards squared B 4840 yards squared C 5445 yards squared D 6345 yards squared

For this case we have that the area of the rectangle is given by:
 A = (w) * (l)
 Where,
 w: width
 l: long
 We use the distance formula between two points:
 d = root ((x2-x1) ^ 2 + (y2-y1) ^ 2)
 We look for the simulations:
 Width:
 w = root ((10-10) ^ 2 + (90-10) ^ 2)
 w = 80
 Long:
 L = root ((10-10) ^ 2 + (10-70.5) ^ 2)
 L = 60.5
 Substituting we have:
 A = (80) * (60.5)
 A = 4840 yd ^ 2
 Answer:
 The area of the plot of land is:
 B 4840 yards squared