I believe that the equation should read:
Max Depth + Bottom Time < 130 = No Decompression Diving on 32%
i.e. if the sum of max depth and bottom time is less than 130, you do not have deco obligations. If it is greater than 130, you might have deco obligations.
As for the example,
70' + 45mins = 115.
115 is less than 130, so it is a no decompression dive.
Max Depth + Bottom Time < 130 = No Decompression Diving on 32%
i.e. if the sum of max depth and bottom time is less than 130, you do not have deco obligations. If it is greater than 130, you might have deco obligations.
As for the example,
70' + 45mins = 115.
115 is less than 130, so it is a no decompression dive.