Step 1: Analyze the inequality.
We are given \( y - x>x + y \). Let's simplify the inequality:
\[
y - x>x + y
\]
Subtract \( y \) from both sides:
\[
-x>x
\]
Multiply both sides by -1:
\[
x<0
\]
This shows that \( x \) must be less than 0. Step 2: Analyze further.
The inequality does not provide any additional restrictions on \( y \), so \( y \) can be either positive or negative. However, we must choose the option that best matches the condition \( x<0 \). Thus, the best answer is (D) \( x<0 \) and \( y>0 \).