Aug 18, 2017 · If signs are the same add the numbers, if signs are different subtract the numbers. Then give the answer the sign of the largest number! - + + - + 3 7 -1 8 13 13. Rules for Multiplying Integers (x) • The product of two integers with the same signs is POSITIVE. • The product of two integers with different signs is NEGATIVE. 14. Add & Subtract Integers lesson plan template and teaching resources. Using a variety of visual aids to help learners understand how to add and subtract integers. Special focus on subtracting negative numbers.