Worksheet for graphing piecewise functions with corresponding equations and blank coordinate planes.
Graphing piecewise functions worksheet with six problems, each requiring graphing a different piecewise function on a coordinate grid.
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Step-by-step solution for: Solved Graphing Piecewise Functions Worksheet f(x) = {x if | Chegg.com
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Show Answer Key & Explanations
Step-by-step solution for: Solved Graphing Piecewise Functions Worksheet f(x) = {x if | Chegg.com
Let's solve each of these piecewise functions step by step. For each function, we will:
1. Graph the function on the given coordinate plane.
2. Determine the domain and range.
---
$$
f(x) =
\begin{cases}
-x & \text{if } x \leq 2 \\
x & \text{if } x > 2
\end{cases}
$$
#### Step-by-step:
- For $ x \leq 2 $: $ f(x) = -x $. This is a line with slope $-1$. It includes $ x = 2 $, so use a closed circle at $ (2, -2) $.
- For $ x > 2 $: $ f(x) = x $. This is a line with slope $1$. Since it's $ x > 2 $, use an open circle at $ (2, 2) $, then draw the ray to the right.
#### Graph:
- Left part: Line $ y = -x $ from left to $ (2, -2) $, closed circle.
- Right part: Line $ y = x $ starting just after $ x = 2 $, open circle at $ (2, 2) $, going up and right.
#### Domain:
All real numbers: $ (-\infty, \infty) $
#### Range:
- For $ x \leq 2 $: $ f(x) = -x $ → as $ x \to -\infty $, $ f(x) \to \infty $; at $ x=2 $, $ f(2) = -2 $
So this part gives values $ [-2, \infty) $
- For $ x > 2 $: $ f(x) = x $ → starts above $ x=2 $, so $ f(x) > 2 $
So this part gives $ (2, \infty) $
But note: $ [-2, \infty) $ already includes $ (2, \infty) $, so overall range is $ [-2, \infty) $
✔ Domain: $ (-\infty, \infty) $
✔ Range: $ [-2, \infty) $
---
$$
f(x) =
\begin{cases}
2 & \text{if } x > -3 \\
-5 & \text{if } x < -3
\end{cases}
$$
Note: There's no definition at $ x = -3 $. So the function is undefined at $ x = -3 $.
- For $ x > -3 $: constant value $ f(x) = 2 $
- For $ x < -3 $: constant value $ f(x) = -5 $
#### Graph:
- Draw horizontal line $ y = 2 $ for $ x > -3 $ → open circle at $ (-3, 2) $
- Draw horizontal line $ y = -5 $ for $ x < -3 $ → open circle at $ (-3, -5) $
- No point at $ x = -3 $
#### Domain:
All real numbers except $ x = -3 $ → $ (-\infty, -3) \cup (-3, \infty) $
#### Range:
Only two values: $ -5 $ and $ 2 $
✔ Domain: $ (-\infty, -3) \cup (-3, \infty) $
✔ Range: $ \{-5, 2\} $
---
$$
f(x) =
\begin{cases}
-1 & \text{if } x \leq -2 \\
2 & \text{if } x > -2
\end{cases}
$$
- For $ x \leq -2 $: constant $ f(x) = -1 $
- For $ x > -2 $: constant $ f(x) = 2 $
#### Graph:
- Horizontal line $ y = -1 $ from left to $ x = -2 $, closed circle at $ (-2, -1) $
- Horizontal line $ y = 2 $ for $ x > -2 $, open circle at $ (-2, 2) $
#### Domain:
All real numbers: $ (-\infty, \infty) $
#### Range:
Values are $ -1 $ and $ 2 $
✔ Domain: $ (-\infty, \infty) $
✔ Range: $ \{-1, 2\} $
---
$$
f(x) =
\begin{cases}
-1 & \text{if } x \leq -1 \\
1 & \text{if } -1 < x < 1 \\
x & \text{if } x > 1
\end{cases}
$$
Break into three parts:
1. $ x \leq -1 $: $ f(x) = -1 $ → horizontal line at $ y = -1 $, closed circle at $ (-1, -1) $
2. $ -1 < x < 1 $: $ f(x) = 1 $ → horizontal line at $ y = 1 $, open circles at both ends: $ (-1, 1) $ and $ (1, 1) $
3. $ x > 1 $: $ f(x) = x $ → line $ y = x $, open circle at $ (1, 1) $, then increasing
#### Graph:
- Left: flat line $ y = -1 $ ending at $ x = -1 $, closed
- Middle: flat line $ y = 1 $ from $ x = -1 $ to $ x = 1 $, open at both ends
- Right: line $ y = x $ starting after $ x = 1 $, open at $ (1,1) $
#### Domain:
All real numbers: $ (-\infty, \infty) $
#### Range:
- From first part: $ y = -1 $
- Second: $ y = 1 $
- Third: $ y = x $ for $ x > 1 $ → $ y > 1 $
So total range: $ \{-1\} \cup \{1\} \cup (1, \infty) = \{-1\} \cup [1, \infty) $
Wait: $ y = 1 $ is included in middle, and $ y > 1 $ from third, so together $ [1, \infty) $
Thus: $ \{-1\} \cup [1, \infty) $
✔ Domain: $ (-\infty, \infty) $
✔ Range: $ \{-1\} \cup [1, \infty) $
---
$$
f(x) =
\begin{cases}
-x + 2 & \text{if } x \leq 0 \\
\frac{1}{2}x + 3 & \text{if } x > 0
\end{cases}
$$
#### Part 1: $ x \leq 0 $, $ f(x) = -x + 2 $
- Slope: $-1$, y-intercept: $2$
- At $ x = 0 $: $ f(0) = -0 + 2 = 2 $ → closed circle at $ (0, 2) $
- Draw line to the left
#### Part 2: $ x > 0 $, $ f(x) = \frac{1}{2}x + 3 $
- Slope: $ \frac{1}{2} $, y-intercept: $3$
- But only for $ x > 0 $, so open circle at $ (0, 3) $
- Then draw line upward to the right
#### Graph:
- Left: line $ y = -x + 2 $ from left to $ (0, 2) $, closed
- Right: line $ y = \frac{1}{2}x + 3 $ starting at $ (0, 3) $, open circle, going up
#### Domain:
All real numbers: $ (-\infty, \infty) $
#### Range:
- Left part: $ x \leq 0 $, $ f(x) = -x + 2 $
- As $ x \to -\infty $, $ f(x) \to \infty $
- At $ x = 0 $, $ f(0) = 2 $
→ So this part gives $ [2, \infty) $
- Right part: $ x > 0 $, $ f(x) = \frac{1}{2}x + 3 $
- At $ x \to 0^+ $, $ f(x) \to 3 $
- As $ x \to \infty $, $ f(x) \to \infty $
→ So this part gives $ (3, \infty) $
Now combine:
- $ [2, \infty) $ from left
- $ (3, \infty) $ from right
But $ [2, \infty) $ already includes $ (3, \infty) $, and also includes $ [2, 3] $
So overall range: $ [2, \infty) $
✔ Domain: $ (-\infty, \infty) $
✔ Range: $ [2, \infty) $
---
$$
f(x) =
\begin{cases}
x + 2 & \text{if } x \leq 2 \\
-\frac{1}{2}x + 4 & \text{if } x > 2
\end{cases}
$$
#### Part 1: $ x \leq 2 $, $ f(x) = x + 2 $
- Slope: $1$, y-intercept: $2$
- At $ x = 2 $: $ f(2) = 2 + 2 = 4 $ → closed circle at $ (2, 4) $
- Draw line to the left
#### Part 2: $ x > 2 $, $ f(x) = -\frac{1}{2}x + 4 $
- Slope: $-\frac{1}{2}$, y-intercept: $4$
- At $ x = 2 $: $ f(2) = -\frac{1}{2}(2) + 4 = -1 + 4 = 3 $, but since $ x > 2 $, open circle at $ (2, 3) $
- Draw decreasing line to the right
#### Graph:
- Left: line $ y = x + 2 $ up to $ (2, 4) $, closed
- Right: line $ y = -\frac{1}{2}x + 4 $ starting after $ x = 2 $, open at $ (2, 3) $, decreasing
#### Domain:
All real numbers: $ (-\infty, \infty) $
#### Range:
- Left part: $ x \leq 2 $, $ f(x) = x + 2 $
- As $ x \to -\infty $, $ f(x) \to -\infty $
- At $ x = 2 $, $ f(2) = 4 $
→ So this part gives $ (-\infty, 4] $
- Right part: $ x > 2 $, $ f(x) = -\frac{1}{2}x + 4 $
- As $ x \to 2^+ $, $ f(x) \to 3 $
- As $ x \to \infty $, $ f(x) \to -\infty $
→ So this part gives $ (-\infty, 3) $
Now combine:
- Left: $ (-\infty, 4] $
- Right: $ (-\infty, 3) $
Union: $ (-\infty, 4] $
✔ Domain: $ (-\infty, \infty) $
✔ Range: $ (-\infty, 4] $
---
| Problem | Domain | Range |
|--------|--------|-------|
| 1 | $ (-\infty, \infty) $ | $ [-2, \infty) $ |
| 2 | $ (-\infty, -3) \cup (-3, \infty) $ | $ \{-5, 2\} $ |
| 3 | $ (-\infty, \infty) $ | $ \{-1, 2\} $ |
| 4 | $ (-\infty, \infty) $ | $ \{-1\} \cup [1, \infty) $ |
| 5 | $ (-\infty, \infty) $ | $ [2, \infty) $ |
| 6 | $ (-\infty, \infty) $ | $ (-\infty, 4] $ |
You can now graph each piece using the descriptions above. Make sure to:
- Use closed circles where the inequality includes equality (≤ or ≥)
- Use open circles where it does not ( < or > )
- Connect appropriately with lines or rays
Let me know if you'd like visual sketches or further explanation!
1. Graph the function on the given coordinate plane.
2. Determine the domain and range.
---
Problem 1:
$$
f(x) =
\begin{cases}
-x & \text{if } x \leq 2 \\
x & \text{if } x > 2
\end{cases}
$$
#### Step-by-step:
- For $ x \leq 2 $: $ f(x) = -x $. This is a line with slope $-1$. It includes $ x = 2 $, so use a closed circle at $ (2, -2) $.
- For $ x > 2 $: $ f(x) = x $. This is a line with slope $1$. Since it's $ x > 2 $, use an open circle at $ (2, 2) $, then draw the ray to the right.
#### Graph:
- Left part: Line $ y = -x $ from left to $ (2, -2) $, closed circle.
- Right part: Line $ y = x $ starting just after $ x = 2 $, open circle at $ (2, 2) $, going up and right.
#### Domain:
All real numbers: $ (-\infty, \infty) $
#### Range:
- For $ x \leq 2 $: $ f(x) = -x $ → as $ x \to -\infty $, $ f(x) \to \infty $; at $ x=2 $, $ f(2) = -2 $
So this part gives values $ [-2, \infty) $
- For $ x > 2 $: $ f(x) = x $ → starts above $ x=2 $, so $ f(x) > 2 $
So this part gives $ (2, \infty) $
But note: $ [-2, \infty) $ already includes $ (2, \infty) $, so overall range is $ [-2, \infty) $
✔ Domain: $ (-\infty, \infty) $
✔ Range: $ [-2, \infty) $
---
Problem 2:
$$
f(x) =
\begin{cases}
2 & \text{if } x > -3 \\
-5 & \text{if } x < -3
\end{cases}
$$
Note: There's no definition at $ x = -3 $. So the function is undefined at $ x = -3 $.
- For $ x > -3 $: constant value $ f(x) = 2 $
- For $ x < -3 $: constant value $ f(x) = -5 $
#### Graph:
- Draw horizontal line $ y = 2 $ for $ x > -3 $ → open circle at $ (-3, 2) $
- Draw horizontal line $ y = -5 $ for $ x < -3 $ → open circle at $ (-3, -5) $
- No point at $ x = -3 $
#### Domain:
All real numbers except $ x = -3 $ → $ (-\infty, -3) \cup (-3, \infty) $
#### Range:
Only two values: $ -5 $ and $ 2 $
✔ Domain: $ (-\infty, -3) \cup (-3, \infty) $
✔ Range: $ \{-5, 2\} $
---
Problem 3:
$$
f(x) =
\begin{cases}
-1 & \text{if } x \leq -2 \\
2 & \text{if } x > -2
\end{cases}
$$
- For $ x \leq -2 $: constant $ f(x) = -1 $
- For $ x > -2 $: constant $ f(x) = 2 $
#### Graph:
- Horizontal line $ y = -1 $ from left to $ x = -2 $, closed circle at $ (-2, -1) $
- Horizontal line $ y = 2 $ for $ x > -2 $, open circle at $ (-2, 2) $
#### Domain:
All real numbers: $ (-\infty, \infty) $
#### Range:
Values are $ -1 $ and $ 2 $
✔ Domain: $ (-\infty, \infty) $
✔ Range: $ \{-1, 2\} $
---
Problem 4:
$$
f(x) =
\begin{cases}
-1 & \text{if } x \leq -1 \\
1 & \text{if } -1 < x < 1 \\
x & \text{if } x > 1
\end{cases}
$$
Break into three parts:
1. $ x \leq -1 $: $ f(x) = -1 $ → horizontal line at $ y = -1 $, closed circle at $ (-1, -1) $
2. $ -1 < x < 1 $: $ f(x) = 1 $ → horizontal line at $ y = 1 $, open circles at both ends: $ (-1, 1) $ and $ (1, 1) $
3. $ x > 1 $: $ f(x) = x $ → line $ y = x $, open circle at $ (1, 1) $, then increasing
#### Graph:
- Left: flat line $ y = -1 $ ending at $ x = -1 $, closed
- Middle: flat line $ y = 1 $ from $ x = -1 $ to $ x = 1 $, open at both ends
- Right: line $ y = x $ starting after $ x = 1 $, open at $ (1,1) $
#### Domain:
All real numbers: $ (-\infty, \infty) $
#### Range:
- From first part: $ y = -1 $
- Second: $ y = 1 $
- Third: $ y = x $ for $ x > 1 $ → $ y > 1 $
So total range: $ \{-1\} \cup \{1\} \cup (1, \infty) = \{-1\} \cup [1, \infty) $
Wait: $ y = 1 $ is included in middle, and $ y > 1 $ from third, so together $ [1, \infty) $
Thus: $ \{-1\} \cup [1, \infty) $
✔ Domain: $ (-\infty, \infty) $
✔ Range: $ \{-1\} \cup [1, \infty) $
---
Problem 5:
$$
f(x) =
\begin{cases}
-x + 2 & \text{if } x \leq 0 \\
\frac{1}{2}x + 3 & \text{if } x > 0
\end{cases}
$$
#### Part 1: $ x \leq 0 $, $ f(x) = -x + 2 $
- Slope: $-1$, y-intercept: $2$
- At $ x = 0 $: $ f(0) = -0 + 2 = 2 $ → closed circle at $ (0, 2) $
- Draw line to the left
#### Part 2: $ x > 0 $, $ f(x) = \frac{1}{2}x + 3 $
- Slope: $ \frac{1}{2} $, y-intercept: $3$
- But only for $ x > 0 $, so open circle at $ (0, 3) $
- Then draw line upward to the right
#### Graph:
- Left: line $ y = -x + 2 $ from left to $ (0, 2) $, closed
- Right: line $ y = \frac{1}{2}x + 3 $ starting at $ (0, 3) $, open circle, going up
#### Domain:
All real numbers: $ (-\infty, \infty) $
#### Range:
- Left part: $ x \leq 0 $, $ f(x) = -x + 2 $
- As $ x \to -\infty $, $ f(x) \to \infty $
- At $ x = 0 $, $ f(0) = 2 $
→ So this part gives $ [2, \infty) $
- Right part: $ x > 0 $, $ f(x) = \frac{1}{2}x + 3 $
- At $ x \to 0^+ $, $ f(x) \to 3 $
- As $ x \to \infty $, $ f(x) \to \infty $
→ So this part gives $ (3, \infty) $
Now combine:
- $ [2, \infty) $ from left
- $ (3, \infty) $ from right
But $ [2, \infty) $ already includes $ (3, \infty) $, and also includes $ [2, 3] $
So overall range: $ [2, \infty) $
✔ Domain: $ (-\infty, \infty) $
✔ Range: $ [2, \infty) $
---
Problem 6:
$$
f(x) =
\begin{cases}
x + 2 & \text{if } x \leq 2 \\
-\frac{1}{2}x + 4 & \text{if } x > 2
\end{cases}
$$
#### Part 1: $ x \leq 2 $, $ f(x) = x + 2 $
- Slope: $1$, y-intercept: $2$
- At $ x = 2 $: $ f(2) = 2 + 2 = 4 $ → closed circle at $ (2, 4) $
- Draw line to the left
#### Part 2: $ x > 2 $, $ f(x) = -\frac{1}{2}x + 4 $
- Slope: $-\frac{1}{2}$, y-intercept: $4$
- At $ x = 2 $: $ f(2) = -\frac{1}{2}(2) + 4 = -1 + 4 = 3 $, but since $ x > 2 $, open circle at $ (2, 3) $
- Draw decreasing line to the right
#### Graph:
- Left: line $ y = x + 2 $ up to $ (2, 4) $, closed
- Right: line $ y = -\frac{1}{2}x + 4 $ starting after $ x = 2 $, open at $ (2, 3) $, decreasing
#### Domain:
All real numbers: $ (-\infty, \infty) $
#### Range:
- Left part: $ x \leq 2 $, $ f(x) = x + 2 $
- As $ x \to -\infty $, $ f(x) \to -\infty $
- At $ x = 2 $, $ f(2) = 4 $
→ So this part gives $ (-\infty, 4] $
- Right part: $ x > 2 $, $ f(x) = -\frac{1}{2}x + 4 $
- As $ x \to 2^+ $, $ f(x) \to 3 $
- As $ x \to \infty $, $ f(x) \to -\infty $
→ So this part gives $ (-\infty, 3) $
Now combine:
- Left: $ (-\infty, 4] $
- Right: $ (-\infty, 3) $
Union: $ (-\infty, 4] $
✔ Domain: $ (-\infty, \infty) $
✔ Range: $ (-\infty, 4] $
---
✔ Summary Table:
| Problem | Domain | Range |
|--------|--------|-------|
| 1 | $ (-\infty, \infty) $ | $ [-2, \infty) $ |
| 2 | $ (-\infty, -3) \cup (-3, \infty) $ | $ \{-5, 2\} $ |
| 3 | $ (-\infty, \infty) $ | $ \{-1, 2\} $ |
| 4 | $ (-\infty, \infty) $ | $ \{-1\} \cup [1, \infty) $ |
| 5 | $ (-\infty, \infty) $ | $ [2, \infty) $ |
| 6 | $ (-\infty, \infty) $ | $ (-\infty, 4] $ |
You can now graph each piece using the descriptions above. Make sure to:
- Use closed circles where the inequality includes equality (≤ or ≥)
- Use open circles where it does not ( < or > )
- Connect appropriately with lines or rays
Let me know if you'd like visual sketches or further explanation!
Parent Tip: Review the logic above to help your child master the concept of algebra 2 piecewise function worksheet.