1. **Stating the problem:** We need to estimate the set of values of $x \in \mathbb{R}$ for which $b(x) < l(x)$ using graphs. 2. **Understanding the problem:** The inequality $b(x) < l(x)$ means we want to find all $x$ values where the graph of $b(x)$ lies below the graph of $l(x)$. 3. **Graph interpretation:** On the graph, identify the regions where the curve of $b(x)$ is under the curve of $l(x)$. 4. **Estimating values:** From the graph, observe the intersection points of $b(x)$ and $l(x)$, say at $x=a$ and $x=b$. 5. **Solution set:** The set of $x$ values where $b(x) < l(x)$ is the interval between these intersection points, i.e., $a < x < b$. 6. **Summary:** Without exact functions or numerical data, the solution is the open interval between the intersection points of $b(x)$ and $l(x)$ on the graph where $b(x)$ is below $l(x)$.