The minimum value of z = 4x = 10y subject to 3x + y <= 24 6x + 4y <= 66 x >= 0, y >= 0 is a. 165 b. 110 c. 44 You mistyped when you typed z = 4x = 10y You must have either meant z = 4x + 10y or else you meant z = 4x - 10 and pressed So we draw the boundary lines from their equations which we form by taking the inequalities and replacing the inequality symbols by equal signs. So we draw the graphs of 3x + y = 24 6x + 4y = 66 x = 0 (the y=axis) y = 0 (the x-axis)If we substitute a point say (1,1) in each original inequality, we will see that the feasible region is the region below the two slanted lines and the two axes. That is this region: If we solve the equations of the two slanted lines we get that they intersect at the point (x,y) = (5,9) That is one of the corner points of the region. The other two corner points are (x,y) = (0,0), (x,y) = (0, 16.5), the y-intercept of 6x + 4y = 66 (x,y) = (8, 0), the x-intercept of 3x + y = 24. Now if you meant z = 4x + 10y, then corner point | x | y | 4x+10y | -------------------------------- (0,0) | 0 | 0 | 0 | (0, 16.5) | 0 | 16.5 | 165 | (5, 9) | 5 | 9 | 110 | (8, 0) | 8 | 0 | 32 | ---------------------------------- Then the minimum value of z is 0 (The maximum value of z is 165). I'm starting to also suspect you may have mistyped "minimum" for "maximum", for 0 is not listed though 165 is listed. Another possibility is that you didn't mistype "minimum" but you mistyped the inequality symbols <=, when you meant >=, which would have given the upper region and then the corner points would have been these, assuming you meant z = 4x + 10y, then corner point | x | y | 4x+10y | -------------------------------- (0, 24) | 0 | 24 | 240 | (5, 9) | 5 | 9 | 110 | (11, 0) |11 | 11 | 44 | ---------------------------------- Then the minimum value would have been 44, which is listed ---------------------------------- Now if you meant z = 4x - 10y, then corner point | x | y | 4x-10y | -------------------------------- (0,0) | 0 | 0 | 0 | (0, 16.5) | 0 | 16.5 | -165 | (5, 9) | 5 | 9 | -70 | (8, 0) | 8 | 0 | 32 | ---------------------------------- Then the minimum value of z is -165 The maximum value of z is 32. But neither of those is listed, unless you mistyped 165 for -165 What is sure is that you mistyped something, but I can't tell what you mistyped. Maybe you can figure out what you mistyped from the above. If not, post again, this time being extremely careful not mistype anything. Edwin