Question: 27. f(x): V-shape opening up with vertex at (0, 0); key points appear at $(-2, 2)$, $(2, 2)$, $(-4, 4)$, and $(4, 4)$.
g(x): V-shape opening down with vertex at $(0, -3)$; key points appear at $(-2, -5)$, $(2, -5)$, $(-4, -7)$, and $(4, -7)$.
1. **Problem Statement:**
We are given two functions:
- $f(x)$ is a V-shaped graph opening upwards with vertex at $(0,0)$ and points $(-2,2)$, $(2,2)$, $(-4,4)$, and $(4,4)$.
- $g(x)$ is a V-shaped graph opening downwards with vertex at $(0,-3)$ and points $(-2,-5)$, $(2,-5)$, $(-4,-7)$, and $(4,-7)$.
2. **Identify the function forms:**
- A V-shaped graph opening up or down is an absolute value function of the form:
$$f(x) = a|x - h| + k$$
where $(h,k)$ is the vertex.
3. **Find $f(x)$:**
- Vertex at $(0,0)$ means $h=0$, $k=0$.
- Use point $(2,2)$ to find $a$:
$$2 = a|2 - 0| + 0 = 2a \implies a = 1$$
- So,
$$f(x) = |x|$$
4. **Find $g(x)$:**
- Vertex at $(0,-3)$ means $h=0$, $k=-3$.
- The graph opens downwards, so $a$ is negative.
- Use point $(2,-5)$:
$$-5 = a|2 - 0| - 3 = 2a - 3$$
$$2a = -5 + 3 = -2 \implies a = -1$$
- So,
$$g(x) = -|x| - 3$$
5. **Summary:**
- $$f(x) = |x|$$
- $$g(x) = -|x| - 3$$
These match the given points and vertex information.