+675 The product of two positive integers minus their sum is 39. The integers are relatively prime, and each is less than 2. What is the sum of the two integers?
+1077
The product of two positive integers minus their sum is 39. The integers are relatively prime, and each is less than 2. What is the sum of the two integers?
A pair that works is (11, 5) so 16 is the sum.
Assuming that "less than 2" is a typo that should have been "less than 20".
Another pair that works is (6, 9) but they aren't relatively prime.
I found them by plotting xy – x – y = 39 on Desmos, then
finding the points where both x and y are positive integers.
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