Change the tax code to a 20% flat tax on ALL income with the current standard deductions only with no tax on less 30k

Throw out all the tax law and start over with a 20% flat tax with standard deductions only. Those making 25k or less pay no tax and from 25k-35k the percentage of the tax goes up by 10%. Example: 27k salary would pay 20% of 20%.
No tax credits, no shelters, ALL income is taxed. Also SSI tax is paid on ALL income with no cap.