CAT Linear Equations

Question

(|x| -3) (|y| + 4) = 12. How many pairs of integers (x, y) satisfy this equation?

1. 4
2. 10
3. 6
4. 8

Answer: Choice (B)

Explanatory Answer

Product of two integers is 12. Further |y| + 4 > 4 . So, we know that one of the numbers has to be greater than 4.

So, we can have

1 x 12 => x = +4, y = +8

2 x 6 => x = +5, y = +2

3 x 4 => x = +6, y = 0

4 + 4 + 2 = 10 possible solutions