The upper boundary on x is 5. Divide this over each endpoint of the y inequality
5/0.25 = 20
5/4 = 1.25
we see that the first result 20 is largest
This means that the upper bound of x/y is 20.
Therefore b = 20.
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The lower boundary on x is -4. Divide this over each endpoint of the y inequality
-4/0.25 = -16
-4/4 = -1
The result -16 is further to the left compared to -1, so therefore it is smaller.
The lower bound of x/y is -16.
This means a = -16.
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We found that a = -16 and b = 20. Therefore, a+b = -16+20 = 4
The final answer is 4
