To analyze the expression \(20 + 16\) and the model described (which has 4 rows of 5 squares and 4 rows of 4 squares), we can interpret it as follows:
- The model with 4 rows of 5 squares represents \(4 \times 5\), which equals 20.
- The model with 4 rows of 4 squares represents \(4 \times 4\), which equals 16.
Combining these, we have: \[ 20 + 16 = 4 \times 5 + 4 \times 4 \]
This can be factored using the distributive property:
\[ = 4 \times (5 + 4) \]
Now, let's check the given options:
- \(4(5) + 4\) is not equivalent because it does not simplify to the original expression.
- \(4 + 5 + 4\) not equivalent to \(20 + 16\).
- \(4(5 + 4)\) is equivalent, as shown.
- \(5(4 + 4)\) also does not match.
Therefore, the expression that is equivalent to the sum \(20 + 16\) is: \[ \boxed{4(5 + 4)} \]