Hello from MrBillDoesMath!
Answer: 4a^2 + 25b^2
Discussion. First, I write the square of a number using the notation "^" which appear on the 6 key of the keyboard. As 3 times 3, or 3 squared, is 9, this becomes 3^2 = 9.
I interpreted you question as asking for the value of
(2a)^2 + (5b) ^ 2 = (2a)(2a) + (5b)(5b) = 4a^2 + 25b^2.
Regards, MrB.
