Key Idea: Scaling Area
When a figure is scaled, its area changes according to the square of the scale factor.
General Rule:
If the linear scale factor is k=, the area scale factor is k^2.
Formula:
New Area = (Scale Factor)^2×Original Area
Doubling a shape’s sides makes its area four times larger; tripling makes it nine times larger, etc.
Why this matters for the SAT:
Scaling problems appear in geometry, especially with similar figures.
Recognizing that area scales with the square of the linear factor prevents mistakes and allows quick calculations of new areas.