Couple different ways to approach this
If all sides are equal you would just add 4 twice, 72 + 8=80, now divide by 4, 20 is the length, width is 4 less than length so subtract 4, 16 is width, now add 2 lengths and 2 widths to double check, 20 + 20 + 16 + 16=72
M = (7, 5)
formula to find mindpoint is
(6,8) = (x1, y1)
(8,2) = (x2,y2)
now substitute those into the formula!
now solve for x & y !!
so now that we have solved for x & y put it in point form and your done !!
point for is (x,y)
and thanks why the Midpoint is (7,5)
1000 = 2*length + 2*wudth
therefore
1000 = 2*150 + 2* width
width = ( 1000 - 300)/2
= 700/2
width = 350
Area = length x width
1,188 = 54 x width
width = 1,188 / 54 = 22 feet