Solution:
If the corresponding ratios of the side lengths are equal, they should form a proportion. You can check this by cross-multiplying.

corresponds to :

corresponds to :

Reminder:
You can use cross products to check if two ratios are equivalent.
= • Set up the proportion.
= • Substitute in the values.
35 ≠ 48 • Cross multiply.
The cross products are not equal, so this is not a proportion. That means the rectangles are not similar.