Find the area ratio of two similar circles from a scale factor
Problem
\(\text{Two}~\text{circles}\) are similar. Using the scale-factor information \(3\), how do their areas compare?
Big Picture
What this problem is really about
Area responds to a dilation in two dimensions, so its factor is the square of the linear scale. We’ll substitute the scaled radius into the circle-area formula, square the entire product, and state the resulting area comparison in the specified direction.
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