Question

PLEASE PLEASE PLEASE HELP!!

Can someone please help me with a step by step of this problem ? I'll seriously appreciate it, and thank you so so so much in advance!!
DON'T ANSWER IF YOU'RE UNSURE!!! I need actual help, please don't just take my points. :c

Answer 1

A^2 to get 45 and b ^2to get 20

Answer 2

A^2=45 so get the sq rat of 45
B^2=20 get the sq rat of 20