which equation represents a direct variation?\no y = 0.5x\no x - y = 5\no xy = 5\no y = x + 5

Answer:

A. $y = 0.5x$

Explanation:

Step1: Recall direct - variation form

The form of a direct variation equation is $y=kx$, where $k$ is a non - zero constant.

Step2: Analyze each option

For $y = 0.5x$, it is in the form $y=kx$ with $k = 0.5$. For $x - y=5$, we can rewrite it as $y=x - 5$, which is not in the form $y=kx$. For $xy = 5$, we can rewrite it as $y=\frac{5}{x}$, which is an inverse variation, not direct. For $y=x + 5$, it is a linear equation but not in the form $y=kx$.