Questions: Use the graph of each equation to test for symmetry with respect to the x-axis, y-axis, and the origin. Support the answer numerically. Then confirm algebraically.
Transcript text: Use the graph of each equation to test for symmetry with respect to the $x$-axis, $y$-axis, and the origin. Support the answer numerically. Then confirm algebraically.
Solution
Solution Steps
Step 1: Identify the given equation
The given equation is \( y = \frac{-2}{x} \).
Step 2: Test for symmetry with respect to the x-axis
To test for symmetry with respect to the x-axis, replace \( y \) with \( -y \) in the equation and see if the equation remains unchanged.
\[ -y = \frac{-2}{x} \]
This simplifies to:
\[ y = \frac{2}{x} \]
Since \( y = \frac{2}{x} \) is not the same as the original equation \( y = \frac{-2}{x} \), the graph is not symmetric with respect to the x-axis.
Step 3: Test for symmetry with respect to the y-axis
To test for symmetry with respect to the y-axis, replace \( x \) with \( -x \) in the equation and see if the equation remains unchanged.
\[ y = \frac{-2}{-x} \]
This simplifies to:
\[ y = \frac{2}{x} \]
Since \( y = \frac{2}{x} \) is not the same as the original equation \( y = \frac{-2}{x} \), the graph is not symmetric with respect to the y-axis.
Step 4: Test for symmetry with respect to the origin
To test for symmetry with respect to the origin, replace \( x \) with \( -x \) and \( y \) with \( -y \) in the equation and see if the equation remains unchanged.
\[ -y = \frac{-2}{-x} \]
This simplifies to:
\[ -y = \frac{2}{x} \]
Multiplying both sides by -1:
\[ y = \frac{-2}{x} \]
Since this is the same as the original equation \( y = \frac{-2}{x} \), the graph is symmetric with respect to the origin.
Final Answer
The graph of the equation \( y = \frac{-2}{x} \) is symmetric with respect to the origin but not symmetric with respect to the x-axis or the y-axis.