Answer: 17 and 25
Explanation:
Let X and Y be the two numbers.
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X + Y = 42 [sum of two numbers is 42]
X - Y = 8 [their difference is 8]
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Rearrange the last equation to
X = 8 + Y
Now enter that into the 1st equation:
X + Y = 42
(8+Y) + Y = 42
2Y = 34
Y = 17
Since X - Y = 8,
X = 8 + 17
X = 25
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X + Y = ?
17 + 25 = 42 Checks
X - Y = ?
25 - 17 = 8 Checks