9514 1404 393
Answer:
vertically stretched by a factor of 4
Explanation:
Each point on the graph is 4 times the distance from the x-axis than it was formerly. The graph is stretched vertically by a factor of 4.
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Additional comment
Here, the transformation g(x) = 4f(x) for f(x) = x² is fully equivalent to g(x) = f(2x). The latter represents a horizontal compression by a factor of 2. That is, each point on the graph moves to half its previous distance from the y-axis.