If X is between -3 and -1, and Y is between -1 and 1

• Numbers

If X is between -3 and -1, and Y is between -1 and 1, then X² - Y² is in between which of the following?

1. -9 and 1
2. -9 and -1
3. 0 and 8
4. 0 and 9

Answer

-3 < X < -1, so 9 < X² < 1

-1 < Y < 1, so 1 < Y² < 1

Subtracting,

8 < X² - Y² < 0

The correct option is C.