They want you plot this system of inequalities


    x + 5y <= 40      (1)

   7x + 5y <= 70      (2)

   x >= 0,  y >= 0    (3)


Plot straight lines in a coordinate plane 


    y =         (1')

    y =        (2')



    


                Plot y =   (red)  and  y =  (green)



Inequalities (3) define the first quadrant QI.



The solution set to the given inequalities (the feasibility domain) are the points of the coordinate plane, 

    that are in QI and, at the same time,  below (or on) the red line  AND  below (or on) the green line.



It is the quadrilateral adjacent to coordinate axes, including its sides and vertices.