Questions: What kind of transformation converts the graph of f(x)=-2x-4 into the graph of g(x)= -8x-4 ?
horizontal stretch
vertical shrink
horizontal shrink
vertical stretch
Transcript text: What kind of transformation converts the graph of $f(x)=-2|x|-4$ into the graph of $g(x)=$ $-8|x|-4$ ?
horizontal stretch
vertical shrink
horizontal shrink
vertical stretch
Solution
Solution Steps
To determine the transformation that converts the graph of \( f(x) = -2|x| - 4 \) into the graph of \( g(x) = -8|x| - 4 \), we need to compare the coefficients of the absolute value terms in both functions. The transformation involves a change in the vertical scaling of the graph. Specifically, the coefficient of \(|x|\) changes from \(-2\) to \(-8\), indicating a vertical stretch by a factor of 4.
Step 1: Identify the Transformation
To determine the transformation from \( f(x) = -2|x| - 4 \) to \( g(x) = -8|x| - 4 \), we compare the coefficients of \(|x|\) in both functions. The coefficient changes from \(-2\) to \(-8\).
Step 2: Analyze the Coefficient Change
The change in the coefficient from \(-2\) to \(-8\) indicates a vertical transformation. Specifically, the absolute value of the coefficient increases from \(2\) to \(8\), which is a factor of \(\frac{8}{2} = 4\).
Step 3: Determine the Type of Transformation
Since the absolute value of the coefficient increases, this indicates a vertical stretch. A vertical stretch occurs when the graph is stretched away from the x-axis by a factor greater than 1.
Final Answer
The transformation that converts the graph of \( f(x) = -2|x| - 4 \) into the graph of \( g(x) = -8|x| - 4 \) is a vertical stretch. Therefore, the answer is \(\boxed{\text{vertical stretch}}\).