The Social Security benefits received plus the small amount of the other income will not be enough for you to be required to file a tax return. None of your income is taxable so there is no need to file a tax return. Unless you have had taxes withheld from the RMD then you should file for a tax refund.
Social Security Retirement/Disability/Survivors benefits becomes taxable when all your other income plus 1/2 your social security reaches:
Married Filing Jointly - $32,000
Single or Head of Household - $25,000
Married Filing Separately - 0
Standard deductions for 2018
Single - $12,000 add $1,600 if age 65 or older
Married Filing Separately - $12,000 add $1,300 if age 65 or older
Married Filing Jointly - $24,000 add $1,300 for each spouse age 65 or older
Head of Household - $18,000 add $1,600 if age 65 or older
