-7+m=8
m=15
How do I show work for this tho?

Maria contrerras earned $53,000 in taxable income. she figured her tax from the single taxpayer table above. 1. find her earned income level. 2. enter the base amount = $ 4,386 3. find the amount over $ 31,850 = $ 5,287.50 4. multiply line 3 by 25% = $ 9,673.50 5. add lines 2 and 4 = $ 21,150