1. **Stating the problem:** We are given a graph with points (0, -4), (1, -6), and (2, 9) and asked to identify the type of sequence or function it represents and find an explicit formula matching the graph.
2. **Analyzing the options:**
- An arithmetic sequence has a constant difference between terms.
- A geometric sequence has a constant ratio between terms.
- A linear function has the form $y = mx + b$ with constant slope.
- An exponential function has the form $y = ab^x$ where $a$ and $b$ are constants and $b > 0$.
3. **Checking the differences:**
- Difference from $x=0$ to $x=1$: $-6 - (-4) = -2$
- Difference from $x=1$ to $x=2$: $9 - (-6) = 15$
Since the differences are not constant, it is not arithmetic or linear.
4. **Checking the ratios:**
- Ratio from $x=0$ to $x=1$: $\frac{-6}{-4} = 1.5$
- Ratio from $x=1$ to $x=2$: $\frac{9}{-6} = -1.5$
Ratios are not constant and also change sign, so it is not geometric.
5. **Conclusion on type:** The graph is non-linear and does not fit arithmetic, geometric, or linear models. The sharp curve suggests an exponential function or another nonlinear function.
6. **Finding an explicit formula:** Assume an exponential function $y = ab^x$.
Using point $(0, -4)$:
$$ -4 = ab^0 = a \implies a = -4 $$
Using point $(1, -6)$:
$$ -6 = -4b \implies b = \frac{-6}{-4} = 1.5 $$
Check point $(2, 9)$:
$$ y = -4(1.5)^2 = -4 \times 2.25 = -9 $$
But the actual $y$ at $x=2$ is 9, not -9, so the exponential model $y = -4(1.5)^x$ does not fit all points.
7. **Alternative approach:** The graph is not a simple exponential function with positive base. The sign change and sharp rise suggest a more complex function or a piecewise function.
8. **Final answer:** The graph cannot be accurately described as arithmetic, geometric, or linear. It is best described as a nonlinear function, possibly exponential-like but not a standard exponential function.
**Summary:** The graph represents a nonlinear function, not arithmetic, geometric, or linear. The explicit formula cannot be a simple exponential $y=ab^x$ with constant $a,b$ matching all points.
**Slug:** nonlinear function
**Subject:** algebra
Nonlinear Function 979471
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.