Annie is self-employed and has $58,000 in income from her business. she also has investments that generated dividends of $3,000 and interest of $2,500. what is annie’s self-employment tax for the year?

First, you need to know the self-employment taxes:
The self-employment tax is 92.35%
Social security tax is 12.4% and Medicare tax is 2.9% = (15.3%)

Dividends and interest are not a part of the income.

58000 * 92.35% *15.3% 
Turn the percentages into decimal form in order to multiply. You can do this by moving the decimals over twice or dividing each percentage by 100. 

58000*.9235 * .153 = $8,195.

Annie's self-employment tax for the year is $8,195.