To determine whether a given graph represents a
function or
not a function, we use the
vertical line test. The vertical line test states:
- If any vertical line intersects the graph at
more than one point, then the graph does
not represent a function.
- If every vertical line intersects the graph at
most one point, then the graph represents a
function.
Let's analyze each graph step by step:
---
Graph 1:
- The graph is a horizontal line.
- A vertical line will intersect this graph at exactly one point.
-
Conclusion: Function
---
Graph 2:
- The graph is a straight diagonal line.
- A vertical line will intersect this graph at exactly one point.
-
Conclusion: Function
---
Graph 3:
- The graph is a parabola that opens to the right.
- A vertical line can intersect this graph at
two points (for example, near the vertex).
-
Conclusion: Not a Function
---
Graph 4:
- The graph is a curve that loops back on itself.
- A vertical line can intersect this graph at
two points (near the loop).
-
Conclusion: Not a Function
---
Graph 5:
- The graph is a piecewise linear function with jumps.
- A vertical line will intersect this graph at exactly one point.
-
Conclusion: Function
---
Graph 6:
- The graph is a parabola that opens upwards.
- A vertical line will intersect this graph at exactly one point.
-
Conclusion: Function
---
Graph 7:
- The graph is an "X" shape (two lines crossing).
- A vertical line can intersect this graph at
two points (where the lines cross).
-
Conclusion: Not a Function
---
Graph 8:
- The graph is a V-shaped absolute value function.
- A vertical line will intersect this graph at exactly one point.
-
Conclusion: Function
---
Graph 9:
- The graph is a zigzag line.
- A vertical line will intersect this graph at exactly one point.
-
Conclusion: Function
---
Final Answers:
1. Function
2. Function
3. Not a Function
4. Not a Function
5. Function
6. Function
7. Not a Function
8. Function
9. Function
Boxed Answer:
\[
\boxed{
\begin{array}{ccc}
1) \text{Function} & 2) \text{Function} & 3) \text{Not a Function} \\
4) \text{Not a Function} & 5) \text{Function} & 6) \text{Function} \\
7) \text{Not a Function} & 8) \text{Function} & 9) \text{Function}
\end{array}
}
\]
Parent Tip: Review the logic above to help your child master the concept of domain and range worksheet.