To determine if the points are solution points to the inequalities which are given:
a) To check (2,9) a solution to y<11−x:
Let us substitute x=2 and y=9, we get
The answer is, No, (2,9) is not a solution to y<11−x.
b) To check (3,9) a solution to y≤15−x:
Put x=3 and y=9 we get,
Since, 9 less than 12.
Hence, the answer is, yes (3,9) is a solution to y≤15−x.
c) To check (4,13) a solution to y>14−x:
Put x=4 and y=13 we get,
Hence, the answer is yes, (4,13) is a solution to y>14−x.
d) To check (5,9) a solution to y≥15−x:
Put x=5 and y=9 we get,
Since, 9 is not greater than 10.
Hence, the answer is No, (5,9) is not a solution to y≥15−x.