Two equations are given
b+t <=9
30b + 20t > 200
WE graph each inequality
b + t <= 9
Make a table for b + t < = 9
b --- > t
0 --> 9
2 --> 7
Plot the point and make a graph. WE shade the bottom region because we have <= symbol
The graph is attached below.
WE graph the inequality
30b + 20t > 200
Make a table for 30b + 20t > 200
b --- > t
0 --> 10
6 --> 1
Plot the point and make a graph. WE shade the upper region because we have > symbol
The intersection of shaded region is our solution.