Hello!
The answer to your question is: 304200.
How to solve:
First determine that 39² = 1521 because 39 × 39 = 1521.
Then, understand 4 + 96 equals 100, but it is asking us for the double of the sum, so multiply 100 by 2, which is 200.
Then all we need is to multiply 1521 by 200.
1521 × 200 = 304200
Hope this answer helps!