Answer: 225
Explanation:
What is a square number?
A square number is a product of a number times itself
So, the 12th square number would be 12 * 12, or 12²
The 9th square number would be 9 * 9, or 9²
The equation would be 12² + 9²
So:
12² + 9²
= 144 + 81
= 225
So, the answer is 225