Radical 63 13 radical 98-5 radical 112

I will assume you mean
\sqrt{63}+13\sqrt{98}-5\sqrt{112} .

You have 63=9\times 7, thus \sqrt{63}=\sqrt{9\times 7}=\sqrt{9}\times\sqrt{7}
=3\sqrt{7} . Similarly \sqrt{98}=7\sqrt{2}=\sqrt{14}\sqrt{7}
and \sqrt{112}=4\sqrt{7}.
From here you can work your way. If you have any doubt repost.