The state income tax on a $90,000 per year salary is: $5175.
Given that the individual makes $90,000 per year, you must use the last bracket, which says "17,001 and up."
That is, you must discover the 5.75% of $90,000 in order to calculate the taxes payable.
Remember that 5.75% is equal to 5.75/100 = 0.0575.
The 5.75% of $90,000 is then calculated technically as the product:
0.0575 x 90,000 = 5175
As a result, the tax on a $90,000 paycheck is $5175