1. **State the problem:** We have two similar pentagons, A and B.
Pentagon A has a base length of 6.4 cm and an area of 97.6 cm².
Pentagon B has a base length of 12.8 cm.
We need to find the area of pentagon B.
2. **Recall the formula for areas of similar shapes:**
If two shapes are similar, the ratio of their areas is the square of the ratio of their corresponding side lengths.
Mathematically, if $\frac{\text{side}_B}{\text{side}_A} = k$, then
$$\frac{\text{Area}_B}{\text{Area}_A} = k^2$$
3. **Calculate the scale factor $k$:**
$$k = \frac{12.8}{6.4} = 2$$
4. **Use the area ratio formula:**
$$\frac{\text{Area}_B}{97.6} = 2^2 = 4$$
5. **Solve for $\text{Area}_B$:**
$$\text{Area}_B = 97.6 \times 4 = 390.4$$
**Final answer:** The area of pentagon B is **390.4 cm²**.
Area Similar Pentagons 409A92
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.