I need little help with this radical expression. I've solved others about 17/18 but this last one just dey tickle my fancy and I've sworn never to rest until I know how they got the correct answer...Please anyone who knows how to solve this should please help me and please try to show working and explaining your thought process so I can understand your solution better.
Thanks in advance, and also thanks to those who helped me with the last problem I posted here...God bless us all.

Please nauuu

sqlPAIN:
I need little help with this radical expression. I've solved others about 17/18 but this last one just dey tickle my fancy and I've sworn never to rest until I know how they got the correct answer...Please anyone who knows how to solve this should please help me and please try to show working and explaining your thought process so I can understand your solution better.
Thanks in advance, and also thanks to those who helped me with the last problem I posted here...God bless us all.

here is the solution.

NDSMELODY:
here is the solution.

. Bro I swear God bless you with immediate effect... Funny thing was that my solution and yours were the same up until the point where I circled out... Stupid me was doing 12-6√5 =6√5 I've been on this shit since yesterday afternoon. Thanks, you just made me understand this thing better, now I no go dey add and subtract anyhow

sqlPAIN:
. Bro I swear God bless you with immediate effect... Funny thing was that my solution and yours were the same up until the point where I circled out... Stupid me was doing 12-6√5 =6√5 I've been on this shit since yesterday afternoon. Thanks, you just made me understand this thing better, now I no go dey add and subtract anyhow

we call the area you circle similar surd because they have thesame root.