The rule: take half of your Social Security and add it to your other income. If this amount exceeds $25000 ($32,000 Married Filing Joint) some of your Social Security will be taxable and included in AGI, but you'll never pay tax on more than 85% of your benefits. In your case, 1/2 Social Security + other income = $19,000 which is less than $25,000, hence none of the Social Security is taxable.
You are correct.
If filing single and the only other income is the $13,000 wages, none of the $12000 from Soc Sec will be taxed.
I have prepared tax returns for nearly 40 years.
Thank you. As far as I can tell, that is the correct solution.