Each question is worth 4 points (100/25=4)
Therefore, when you divide 83 by 4, you get 20.75, as as he's aiming to get a B, this needs to be rounded up to 21.
Xio would need to get 21 questions right to get a B, hope this helps :)
Answer:
(see image)
bottom right image
Explanation:
First try the origin (0,0) to rule out two of the graphs.
3y ≥ x - 9 3(0) ≥ (0) - 9
3 ≥ - 9
yes 3x + y > - 3 3(0) + (0) > - 3
3 > - 3
yes so the origin should be in the shaded area of the graph, which rules out the top right and bottom left graphs.
Now try a coordinate that is in the shaded area of one of the remaining graphs, but not in the other one. If it works, the graph is the one that has that point in the shaded region, and vice versa.
Try point (4, 2)
3y ≥ x - 9
3(2) ≥ (4) - 9
6 ≥ - 5
yes3x + y > - 3
3(4) + (2) > - 3
12 + 2 > - 3
14 > - 3
yesSo the graph is the bottom right one since (4, 2) is included in that shaded region.
4 5/12 you just add the fractions