Question

lesson 12 checkpoint
listen
kiara is drawing a photo of a car using a scale factor of 3. the radius for each of the cars tires is 2 cm. what will the area of a tire in kiaras drawing be?
168 cm²
113 cm²
56.5 cm²
12.6 cm²

Explanation:

Step1: Find the radius in the drawing

Multiply the actual - radius by the scale factor. Given the actual radius $r = 2$ cm and scale factor $k = 3$, the radius in the drawing $R=k\times r=3\times2 = 6$ cm.

Step2: Calculate the area of the tire in the drawing

Use the formula for the area of a circle $A=\pi R^{2}$. Substitute $R = 6$ cm into the formula, $A=\pi\times6^{2}=36\pi\approx36\times 3.14 = 113.04\approx113$ $cm^{2}$.

Answer:

113 $cm^{2}$