An enlargement with centre the origin and scale factor 3 maps the triangle of area 4 cm2 onto its image. What is the area of the image?
Answer and explanation
Correct answer: C. 36 cm2
- Step 1: Area scale factor = (linear scale factor) squared = 9. Step 2. Image area = 4 x 9 = 36 cm2. Answer: 36 cm2. Why not the others: 12 cm2: That multiplies the area by the scale factor only once. 7 cm2: That adds 3 to the area. 108 cm2: That multiplies by the scale factor cubed.
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