Answer:
-0.75 or -3/4 (if you prefer fractions)
Step-by-step explanation:
We should start off with knowing that the slope is the change of Y over the change of X. There's not enough detail in this graph, so we need to find an area in which we hit the point.
We find this by rising (or falling if you prefer) 3 on the Y axis and running 4 on the X axis, hitting a point. We can safely say that the slope here is the change of Y over the change of X (as previously stated) which is -3/5, or -0,75 for each X variable, as we go downwards.
Edit: The full equation would be y = -0.75x (without any + b since the y-intercept is the origin point or starting point, 0,0, and it would be redundant to say y = -0.75x + 0).
