50 & -15 is your answer
To find the sum of these two numbers, add them:
50 + (-15) = 35
50 - 15 = 35
35 = 35 (True)
To find the difference of these two numbers, subtract them. Note that two negatives = one positive:
50 - (-15) = 65
50 + 15 = 65
65 = 65 (True)
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