Hi,
I've discussed this question before but it was taking too long to find my old post. We can solve more quickly by reasoning through the concept of absolute value rather than relying on pure algebra:
Is x > 0?
(1) |x + 3| = 4x - 3
We see the absolute value bars on the left. We know that absolute value is always positive or zero. We also know that, by definition, the left hand side of an equation must equal the right hand side. Therefore:
4x - 3 >= 0
x >= 3/4
If x is greater than or equal to 3/4, then it is definitely greater than 0.
SUFFICIENT.
(2) |x + 1| = 2x - 1
Similarly,
2x - 1>=0
x>= 1/2
SUFFICIENT.
Choose D.
Kaplan Teacher in Toronto