The area between the hyperbola , then x – axis and the ordinates at a and b with a > b is :


Objective function is Z = x + 2 y ……………………(1).
The given constraints are : 2x + y ≥ 3, x + 2y ≥ 6, x, y ≥ 0 .
Corner points | Z = x + 2y |
A(0 ,3 ) | 6…………………..(Minimum) |
B(6,0) | 6………………………(Minimum) |
Here , Z = 18 is minimum at ( 0, 3 ) and ( 6 , 0 ) .
Minimum Z = 6 at all the points on the line segment joining the points (6, 0) and (0, 3).




The equation 4x + 5y = 20 can be written as + = 1
This implies the intercepts cut by this line on the X and Y axes are 5 and 4 respectively.
Hence the area of the triangle is 1/2 [ 5 x 4] = 10 square units
Since
Hence tautology