yu hav a rektangel 300 ft bi 400ft.... apparentlee guvt gonna take a 60ft wide band out along the DIAGONAL... mi ges is yu wanna no how much land will be left... 1. start area=300*400=120,000 sq ft... 2. diagonal length=500 ft (start time)... yu will be left with 2 identikal rite triangels av same size & shape (3-4-5)... need tu find size av nu triangels wen muev 30 ft perpendikular tu diagonal... slope av diagonal=300/400=3/4, so perp line slope=-4/3... if yu go 30 ft in this direkshun, y-part=-4/5 & x-part=-3/5... deltax=(30ft)*(-3/5)=-90/5=-18ft; so nu leng=400-18=382 ft... deltay=(30ft)*(-4/5)=-120/5=-24ft; nu hite=300-24=276... nu area=276*382=105,432... loss=120,000 - 105,432=14,568