1. **Problem Statement:**
(a) Sketch the graph of $y = |2x + 1|$.
(b) Solve the inequality $3x + 5 < |2x + 1|$.
2. **Understanding the absolute value function:**
The function $y = |2x + 1|$ is an absolute value function, which creates a "V" shape graph.
The vertex occurs where the inside of the absolute value is zero:
$$2x + 1 = 0 \implies x = -\frac{1}{2}$$
3. **Piecewise definition of the function:**
For $x \geq -\frac{1}{2}$, the function is:
$$y = 2x + 1$$
For $x < -\frac{1}{2}$, the function is:
$$y = -(2x + 1) = -2x - 1$$
4. **Sketching the graph:**
- Plot the vertex at $\left(-\frac{1}{2}, 0\right)$.
- For $x \geq -\frac{1}{2}$, graph the line $y = 2x + 1$.
- For $x < -\frac{1}{2}$, graph the line $y = -2x - 1$.
5. **Solving the inequality $3x + 5 < |2x + 1|$:**
We consider two cases based on the definition of the absolute value.
**Case 1: $x \geq -\frac{1}{2}$**
$$3x + 5 < 2x + 1$$
Subtract $2x + 1$ from both sides:
$$3x + 5 - (2x + 1) < 0$$
$$x + 4 < 0$$
$$x < -4$$
But this contradicts $x \geq -\frac{1}{2}$, so no solution in this case.
**Case 2: $x < -\frac{1}{2}$**
$$3x + 5 < -2x - 1$$
Add $2x + 1$ to both sides:
$$3x + 5 + 2x + 1 < 0$$
$$5x + 6 < 0$$
$$5x < -6$$
$$x < -\frac{6}{5}$$
Since $x < -\frac{1}{2}$, the solution here is:
$$x < -\frac{6}{5}$$
6. **Final solution:**
The solution to the inequality is:
$$\boxed{x < -\frac{6}{5}}$$
Abs Value Inequality D0C699
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