Have i figured out this surd equation correctly

<245> + <363> +2 <12> - <80>

<49x5> + <121x3> +2 <4x3> - <16x5>
7 <5> + 11 <3> + 2x2 <3> - 4 <5>

(7+11+4-4) <5> <3>
= 18 <5> <3>

The numbers in these brackets <> is meaning the square root symbol

Have i done this correctly? And if not can you tell me where i went wrong and how to do it properly? Thank you.

Not quite right... You can't add the factors in front of different roots.

7 <5> + 11 <3> + 2x2 <3> - 4 <5>
= (7-4) <5> + (11+4) <3>
= 3 <5> + 15 <3>

...which means I was wrong earlier... oh well, everyone makes mistakes.

I am going to assume this is your problem and that the question asks you to simplify.

245^1/2 + 363^3 + 2(12)^1/2 - 80^1/2

The problem is on your third step you have added unlike terms. It should be

3 x 5^1/2 + 15 x 3^1/2