Question

Help! How do you do it?

Answer 1

Here you should add the like terms; so 6 + 3 = 9 and 5*(sq.root of 5) - 2*(sq.root of 5) = 3*(sq.root of 5), therefor the answer would be 3*(sq.root of 5) + 9

Remember that surds can be added or subtracted if the term underneath the square root sign is the same :)