To find the integer whose square root is close to \( \frac{9}{4} \), we first calculate \( \frac{9}{4} \):
\[ \frac{9}{4} = 2.25 \]
Next, we want to find the integer \( x \) such that:
\[ \sqrt{x} \approx 2.25 \]
To find \( x \), we can square \( 2.25 \):
\[ x \approx (2.25)^2 \]
Calculating \( (2.25)^2 \):
\[ (2.25)^2 = 5.0625 \]
The closest integer to \( 5.0625 \) is \( 5 \).
Thus, the integer whose square root is close to \( \frac{9}{4} \) is \( 5 \).