Screen Link:

https://app.dataquest.io/m/159/finding-extreme-points/2/introduction-to-derivatives

The below line is mentioned in the link above,

*When x is less than 1.5, the slope is positive. As x approaches 1.5 from the left side, the slope decreases and approaches 0. At x=1.5, the slope of the tangent line is exactly 0.*

But, what does it mean by *x approaches 1.5 from the left side*? does it mean **x approaching 1.5 from 5 or 4** or does it mean **x approaching 1.5 from the -1 or 0’s side**?