Asked by Alto Saxaphone

How do i apply the vertical test to determine if a relation is a function?

Answers

Answered by Alto Saxaphone
So if a graph shows a curve with y plot points at -6 and 6 and an x plot point at 6, its a function?
Answered by Alto Saxaphone
How can you tell the ordered pair for an equation like y = [frac/] -2/3x + 6?
Answered by Alto Saxaphone
How can you tell if a function is proporsional
Answered by GPT-4o mini
The vertical line test is a visual way to determine whether a relation is a function. According to the definition of a function, each input (or x-value) must correspond to exactly one output (or y-value).

To apply the vertical line test, follow these steps:

1. **Graph the relation**: Plot the points of the relation on a coordinate system or draw the curve if it's defined by an equation.

2. **Draw vertical lines**: Imagine drawing vertical lines (or use a ruler or a straight edge) that can move across the graph from left to right.

3. **Check for intersections**: If any vertical line intersects the graph at more than one point, then the relation is **not** a function. This means that for the x-value corresponding to the intersection points, there are multiple y-values (outputs).

4. **If no vertical line intersects more than once**: If every vertical line intersects the graph at most once, then the relation **is** a function. This indicates that each x-value has a unique y-value.

### Example
- **Example of a function**: The graph of \( y = x^2 \) passes the vertical line test, as any vertical line will intersect the graph at most once.

- **Example of not a function**: The graph of a circle, like \( x^2 + y^2 = r^2 \), fails the vertical line test because there are vertical lines that intersect the circle at two points, indicating that some x-values map to multiple y-values.

Using the vertical line test is a straightforward way to visually determine whether a relation is a function.
Answered by GPT-4o mini
To determine if the described graph represents a function, we can apply the vertical line test.

1. **Understanding the points**: You mentioned that for an x-coordinate of 6, there are two different y-values: -6 and 6. This means that at \( x = 6 \), the relation has the points (6, -6) and (6, 6).

2. **Applying the vertical line test**: If you draw a vertical line at \( x = 6 \), it will intersect the graph at both points (6, -6) and (6, 6).

Since a vertical line intersects the graph at two points for that specific x-value, this indicates that there are multiple y-values (outputs) for the same x-value (input).

Therefore, according to the vertical line test, the relation is **not a function**.

In summary, a relation that assigns more than one output (y-value) for a single input (x-value) fails the definition of a function. In this case, it is not a function.
Answered by GPT-4o mini
It looks like you're trying to describe a linear equation in slope-intercept form, which is typically written as:

\[
y = mx + b
\]

where \( m \) is the slope and \( b \) is the y-intercept.

In your example, the equation appears to have a formatting issue, but it seems like it may be written as:

\[
y = -\frac{2}{3}x + 6
\]

This indicates:
- The slope \( m = -\frac{2}{3} \)
- The y-intercept \( b = 6 \) (which means the graph intersects the y-axis at the point (0, 6)).

From this equation, you can derive various ordered pairs (points) that satisfy the equation by substituting different x-values and calculating the corresponding y-values. Here’s how to find some ordered pairs:

1. **Choose x-values**: Pick any values for \( x \). Common choices include integers like -3, -2, -1, 0, 1, 2, 3, etc.

2. **Calculate y-values**: Plug these x-values into the equation and solve for \( y \).

### Example Ordered Pairs

1. **For \( x = 0 \)**:
\[
y = -\frac{2}{3}(0) + 6 = 6.
\]
Ordered pair: **(0, 6)**.

2. **For \( x = 3 \)**:
\[
y = -\frac{2}{3}(3) + 6 = -2 + 6 = 4.
\]
Ordered pair: **(3, 4)**.

3. **For \( x = -3 \)**:
\[
y = -\frac{2}{3}(-3) + 6 = 2 + 6 = 8.
\]
Ordered pair: **(-3, 8)**.

4. **For \( x = 6 \)**:
\[
y = -\frac{2}{3}(6) + 6 = -4 + 6 = 2.
\]
Ordered pair: **(6, 2)**.

5. **For \( x = -6 \)**:
\[
y = -\frac{2}{3}(-6) + 6 = 4 + 6 = 10.
\]
Ordered pair: **(-6, 10)**.

### Summary
You can generate an infinite number of ordered pairs \((x, y)\) that satisfy the equation by selecting different values for \( x \) and calculating the corresponding \( y \) values using the equation \( y = -\frac{2}{3}x + 6\).
Answered by GPT-4o mini
A function is proportional if it can be expressed in the form

\[
y = kx
\]

where \( k \) is a non-zero constant. This means that the relationship between \( y \) and \( x \) is linear, passing through the origin (0,0), with a constant ratio of \( y \) to \( x \) for any pair of corresponding values.

Here are a few criteria to determine if a function is proportional:

### 1. **Linear Equation Through the Origin**
- The equation of a proportional relationship is linear and has no constant term (intercept). It must pass through the origin (0, 0), which means when \( x = 0 \), \( y \) should also be \( 0 \).

### 2. **Constant Ratio**
- For any two points \((x_1, y_1)\) and \((x_2, y_2)\) on the graph of the function, the ratio \( \frac{y_1}{x_1} \) should be equal to \( \frac{y_2}{x_2} \). In other words, the output \( y \) is always some constant multiple (the constant of proportionality \( k \)) of the input \( x \).
- You can check the ratio using any data points:
\[
k = \frac{y}{x}
\]

### 3. **Graph Characteristics**
- If you plot the function on a graph, a proportional function will appear as a straight line that passes through the origin. Any deviation from this will indicate that the function is not proportional.

### 4. **Equation Check**
- If you have a function in the form \( y = mx + b \) (where \( m \) is the slope and \( b \) is the y-intercept):
- If \( b = 0 \), then the function is proportional.
- If \( b \neq 0 \), then the function is not proportional.

### Example
1. **Proportional Function**:
- \( y = 3x \) — passes through the origin and has a constant ratio (\( \frac{y}{x} = 3 \)).

2. **Not a Proportional Function**:
- \( y = 2x + 1 \) — does not pass through the origin (the y-intercept is 1) and the ratio \( \frac{y}{x} \) changes at different points.

In summary, to determine if a function is proportional, check for a linear relationship that passes through the origin, maintain a constant ratio of \( y \) to \( x \), and ensure no constant term is present in the equation.

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