Question: Graph the following.
$f(x)=\begin{cases}-\frac{2}{3}x+1, \text{ for } x<3,\\ -1, \text{ for } x\geq 3\end{cases}$
Choose the correct graph below.
A.
B.
C.
D.
Graph shape: a decreasing line with y-intercept 1 ending with an open circle at $(3,-1)$, and a horizontal ray at $y=-1$ for $x\geq 3$ with a closed circle at $(3,-1)$; position_hint = center
1. **State the problem:** We need to graph the piecewise function:
$$f(x)=\begin{cases}-\frac{2}{3}x+1, & x<3 \\ -1, & x\geq 3\end{cases}$$
2. **Understand the pieces:**
- For $x<3$, the function is a line with slope $-\frac{2}{3}$ and y-intercept $1$.
- For $x\geq 3$, the function is constant at $-1$.
3. **Calculate the value at $x=3$ for the first piece:**
$$f(3) = -\frac{2}{3} \times 3 + 1 = -2 + 1 = -1$$
4. **Interpret the open and closed circles:**
- At $x=3$, the first piece ends with an open circle at $(3,-1)$ because it is defined only for $x<3$.
- The second piece starts at $x=3$ with a closed circle at $(3,-1)$ because it is defined for $x\geq 3$.
5. **Graph description:**
- Draw the line $y = -\frac{2}{3}x + 1$ for $x<3$ ending with an open circle at $(3,-1)$.
- Draw a horizontal ray at $y=-1$ starting at $x=3$ with a closed circle at $(3,-1)$ extending to the right.
6. **Final answer:** The correct graph matches the description: a decreasing line with y-intercept $1$ ending with an open circle at $(3,-1)$, and a horizontal ray at $y=-1$ for $x\geq 3$ with a closed circle at $(3,-1)$.