Investors & landlords

Going to add to this convo for 2018 taxes.

Ignoring deductions and the 3.8% NIIT, if my adjusted gross income is $425,800 and LTCG are also $425,800, my tax rate is 15% correct?

What if my AGI/LTCG are $425,801? Does the extra dollar make all of it taxed at 20%, or only the additional $1? Thanks.