Let’s solve each problem step by step, explaining
domain,
range, and whether the relation is a
function.
---
🔹 Definitions Recap:
-
Domain: The set of all
input values (x-values) in the relation.
-
Range: The set of all
output values (y-values) in the relation.
-
Function: A relation where
each x-value maps to exactly one y-value.
→ If any x-value appears more than once with *different* y-values, it is
NOT a function.
---
##
✔ Problem 1: {(2,3), (-1,5), (0,-1), (3,5), (5,0)}
Step 1: Extract x-values → Domain
x-values: 2, -1, 0, 3, 5
→
Domain = {-1, 0, 2, 3, 5} *(usually written in ascending order)*
Step 2: Extract y-values → Range
y-values: 3, 5, -1, 5, 0
→ Remove duplicates: 3, 5, -1, 0
→
Range = {-1, 0, 3, 5}
Step 3: Is it a function?
Check if any x-value repeats with a different y-value.
All x-values are unique → Each x maps to only one y.
→
Function: YES
---
##
✔ Problem 2: Mapping Diagram
x: 2 → y: -2
x: 4 → y: 0
x: 5 → y: 2
x: 9 → y: 4
Domain: All x-values → {2, 4, 5, 9}
Range: All y-values → {-2, 0, 2, 4}
Function?
Each x maps to only one y →
YES
---
##
✔ Problem 3: Mapping Diagram
x: -3 → y: 1
x: 1 → y: 0
x: 3 → y: 2
x: 5 → y: 3
*(Note: The diagram shows arrows from x to y — each x has only one arrow.)*
Domain: {-3, 1, 3, 5}
Range: {0, 1, 2, 3}
Function?
Each x maps to exactly one y →
YES
---
##
✔ Problem 4: Graph with points on coordinate plane
We need to read the coordinates of each point.
Looking at the graph (assuming standard grid with integer coordinates):
Points appear to be:
- (-3, -2)
- (-2, 1)
- (-1, 3)
- (0, 2)
- (1, -1)
- (2, 0)
- (3, 1)
*(You may need to count carefully — but based on typical worksheet design, these are reasonable estimates.)*
Domain: All x-values → {-3, -2, -1, 0, 1, 2, 3}
Range: All y-values → {-2, -1, 0, 1, 2, 3}
Function?
Check for repeated x-values with different y-values → All x-values are unique →
YES
---
##
✔ Problem 5: Graph with points on coordinate plane
Points appear to be:
- (-3, 0)
- (-2, 2)
- (-1, 1)
- (0, -1)
- (1, 0)
- (2, -2)
- (3, 1)
*(Again, assuming standard grid.)*
Domain: {-3, -2, -1, 0, 1, 2, 3}
Range: {-2, -1, 0, 1, 2}
Function?
All x-values are unique → Each x maps to one y →
YES
---
## 📝 Final Answers:
---
1.
Domain:
{-1, 0, 2, 3, 5}
Range:
{-1, 0, 3, 5}
Function:
yes
---
2.
Domain:
{2, 4, 5, 9}
Range:
{-2, 0, 2, 4}
Function:
yes
---
3.
Domain:
{-3, 1, 3, 5}
Range:
{0, 1, 2, 3}
Function:
yes
---
4.
Domain:
{-3, -2, -1, 0, 1, 2, 3}
Range:
{-2, -1, 0, 1, 2, 3}
Function:
yes
---
5.
Domain:
{-3, -2, -1, 0, 1, 2, 3}
Range:
{-2, -1, 0, 1, 2}
Function:
yes
---
✔ Note: In all 5 problems, every x-value is unique → so all are functions. This is common in introductory worksheets to build confidence before introducing non-functions (like vertical lines or repeated x-values).
Let me know if you’d like to see how to identify a *non*-function example!
Parent Tip: Review the logic above to help your child master the concept of domain and range of functions worksheet.