I. Addition

A. If you are adding and the signs are the same: add and keep the sign.

B. If you are adding and the signs are different: subtract and keep the sign of the larger.

II. Subtraction {In general, subtracting is equal to adding the opposite}

A. Subtracting (a positive) is equal to adding the negative.

B. Subtracting a negative is equal to adding the positive.

III. Multiplication / Division {First, you simply multiply (or divide) the digits and then …}

A. If the signs are the same: the product (or quotient) will be positive.

B. If the signs are different: the product (or quotient) will be negative.