Using Positive and Negative Numbers

Addition --
  1. (+3) + (+5) = (+8) -- The signs are both plus, thus add the digits and write a plus value.
  2. (-3) + (+5) = (+2) -- The signs are different, thus take the difference between the digits and write the sign of the larger digit.
  3. (-3) + (-5) = (-8) -- The signs are both minus, thus add the digits and write a negative value.
  4. (+3) + (-5) = (-2) -- The signs are different, thus take the difference between the digits and write the sign of the larger digit.

Subtraction --

  1. (+3) - (+5) = +3 - 5 = (-2) -- Change the sign before the second digit. Take the difference between the digits and write the sign of the larger digit.
  2. (-3) -(+5) = -3 - 5 = (-8) -- Change the sign before the second digit. Add the digits and write a negative value.
  3. (-3) - (-5) = -3 +5 = (+2) -- Change the sign before the second digit. Take the difference between the digits and write the sign of the larger digit.
  4. (+3) - (-5) = +3 +5 = (+8) -- Change the sign before the second digit. Add the digits and write a positive value.

Multiplication --

  1. (+6) x (+3) = (+18) -- The signs are both plus, thus multiply and add a plus value.
  2. (+6) x (-3) = (-18) -- The signs are different, thus multiply and add a minus value.
  3. (-6) x (-3) = (+18) -- The signs are both minus, thus multiply and add a plus value.
  4. (-6) x (+3) = (-18) -- The signs are different, thus multiply and add a minus value.
Division --
  1. (+6) ÷ (+3) = (+18) -- The signs are both plus, thus divide and add a plus value.
  2. (+6) ÷ (-3) = (-18) -- The signs are different, thus divide and add a minus value.
  3. (-6) ÷ (-3) = (+18) -- The signs are both minus, thus divide and add a plus value.
  4. (-6) ÷ (+3) = (-18) -- The signs are different, thus divide and add a minus value.