Let's go through each of the given points and plug in the coordinates
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Plug in (x,y) = (-2,-5)
5x + 5y > 45
5(-2) + 5(-5) > 45 ... replace x with -2; replace y with -5
-10 - 25 > 45
-35 > 45
The last inequality is false, so (-2,-5) is not in the solution set.
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Plug in (x,y) = (0, 10)
5x + 5y > 45
5*0 + 5*10 > 45
0 + 50 > 45
50 > 45
The last inequality is true so (0,10) is in the solution set
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Plug in (x,y) = (5,8)
5x + 5y > 45
5*5 + 5*8 > 45
25+40 > 45
65 > 45
The last inequality is true so (5,8) is in the solution set
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Plug in (x,y) = (8,-3)
5x + 5y > 45
5*8 + 5*(-3) > 45
40 - 15 > 45
25 > 45
The last inequality is false, so (8,-3) is not in the solution set
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Summary: The points (0, 10) and (5,8) are in the solution set
Check out the attached image to see a visual representation of this.
Notice how point B and point C are in the red shaded region.