Answer: 49
reason:
okay so basically to get to 3 to 5 you have to add 2. To get to 21 to 35 you need to add 14. To get to 5 to 7 you need to add 2, therefore adding 14 to 35. It's a pattern :)
The only other possible meaning I can see is that a2 + b2 means a^2 + b^2. In the case that is a formula that cannot be simplified further, although it could be written as (a + b)^2 - 2ab or (a - b)^2 + 2ab. ... Originally Answered: What is the formula of a2+b2?
You could turn the fraction into a decimal and then see which is bigger