Find the perimeter of the polygon defined by the coordinates (5, 8), (12, 0), (-5, 0), and (-1, 8). (round to nearest tenth)
a) 42.5 units
b) 42.6 units
c) 47.5 units
d) 47.6 units

The answer is B. 42.6 units. To solve this, plot the points in a coordinate plane. Then get the distances between points. It is noted that lines (-1,8) to (5,8) and (-5,0) to (12,0) are straight lines. To get the distance, count the value from X1 to X2 since the lines are bounded by the 8 and 0 Y-coordinates respectively. The distances are 6 and 17. Next is to get the values of the diagonal lines (5,8) to (2,0) and (-1,8) to (-5,0). Use the distance formula D^2 = (X1-X2)^2 + (Y1-Y2)^2. Using the coordinates (5,8) to (12,0); substitute the values into the equation. D^2 = (5-12)^2 + (8-0)^2. The equation becomes D^2 = 113. Next, get the square root of D and 113 to get the distance. The value of D is 10.63. Repeating the same steps to coordinates (-1,8) to (-5,0), the distance of the line is 8.94 units. Haveing all the line distances, add all the values. The sum of the values is 42.57 units. Round it off the the nearest tenths place, the value becomes 42.6 units.