A new fence is constructed on three sides of a housing block with area 240 m2. the fourth side facing the road is left open. if 52 m of fencing is used, what are the dimensions of the block?
Suppose the side parallel to the open side be y m and each of the other two sides be x m thus 2x+y=52 hence y=52-2x
area is given by: area=xy x(52-2x)=240 re-writing the above we get -2x^2+52x-240=0 x^2-26x+120=0 factoring the above we get: (x-20)(x-6)=0 thus x=20 or x=6 if x=20, then y=52-40=12 if x=6, then y=52-12=40
