In the given figure, feasible region represented by the constraints $4x + y ≥80, x+5y≥ 115, 3x + 2y ≤ 150, x, y ≥ 0$ is |
Region A Region B Region C Region D |
Region C |
The correct answer is Option (3) → Region C Given constraints $4x+y\ge80$ $x+5y\ge115$ $3x+2y\le150$ $x\ge0,\;y\ge0$ Find intersection points of boundary lines Intersection of $4x+y=80$ and $x+5y=115$ $y=80-4x$ $x+5(80-4x)=115$ $x+400-20x=115$ $-19x=-285$ $x=15$ $y=20$ Point $(15,20)$ Intersection of $4x+y=80$ and $3x+2y=150$ $y=80-4x$ $3x+2(80-4x)=150$ $3x+160-8x=150$ $-5x=-10$ $x=2$ $y=72$ Point $(2,72)$ Intersection of $x+5y=115$ and $3x+2y=150$ $x=115-5y$ $3(115-5y)+2y=150$ $345-15y+2y=150$ $-13y=-195$ $y=15$ $x=40$ Point $(40,15)$ Intersection with axes From $4x+y=80$, at $x=0$, $y=80$ but does not satisfy $x+5y\ge115$ From $x+5y=115$, at $y=0$, $x=115$ but violates $3x+2y\le150$ From $3x+2y=150$, at $x=0$, $y=75$ but violates $x+5y\ge115$ Hence feasible corner points are $(2,72),\;(15,20),\;(40,15)$ The feasible region is the triangular region with vertices $(2,72),\;(15,20),\;(40,15)$. |