Question

the polygons are similar. the area of one polygon is given. find the area of the other polygon.
4 cm
$a = 10\\ \text{cm}^2$
12 cm
area $= \square\\ \text{cm}^2$

Explanation:

Step1: Find similarity ratio

$\text{Ratio} = \frac{12}{4} = 3$

Step2: Find area scale factor

$\text{Scale factor} = 3^2 = 9$

Step3: Calculate new area

$\text{New Area} = 10 \times 9 = 90$

Answer:

$90$ cm²