Answer
D
Work Step by Step
We will have to consider some points in order to match the differential equation with its graph, such as:
a) When $x=-y$, then the slope becomes null (zero), therefore, this eliminates the both graphs A and C.
b. When we look at the positive values of $x$ and $y$ , then we can see that the slope also becomes positive,so this eliminates the graph for B.
Hence, the graph is ${D}$
