Which of the points is NOT one of the vertices (s,t) of the shaded region of the set of inequalities shown below?
Please help
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Answer:
Option D
Step-by-step explanation:
Given: set of inequalities
To find: Points which do not satisfy all the inequalities
Solution:
For point [tex](15,0)[/tex]:
[tex]15\leq 30-3(0)=30\\15\geq 15-0=15\\15\leq 25-0=25\\15\geq 0\\0\geq 0[/tex]
So, (15, 0) satisfies all the inequalities
For point [tex](7.5,7.5)[/tex]:
[tex]7.5\leq 30-3(7.5)=30-22.5=7.5\\7.5\geq 15-7.5=7.5\\7.5\leq 25-7.5=17.5\\7.5\geq 0\\7.5\geq 0[/tex]
So, (7.5, 7.5) satisfies all the inequalities
For point (22.5,2.5):
[tex]22.5\leq 30-3(2.5)=30-7.5=22.5\\22.5\geq 15-2.5=12.5\\22.5\leq 25-2.5=22.5\\22.5\geq 0\\2.5\geq 0\\[/tex]
So, (22.5,2.5) satisfies all the inequalities
For point (7.5 ,0):
Put s = 7.5 and t = 0 in [tex]s\geq 15-t[/tex]
[tex]7.5\geq 15-0=15[/tex] which is false
So, [tex](s,t)\neq (7.5,0)[/tex]