If X \(\ast\) Y = X + Y – XY, find x when (x \(\ast\) 2) + (x \(\ast\) 3) = 68
- 24
- 22
- -12
-
-21
The correct answer is: D
Explanation
x \(\ast\) y = x + y - xy
(x \(\ast\) 2) + (x \(\ast\) 3) = 68
= x + 2 - 2x + x + 3 - 3x = 68
-3x = 63
x = -21