Question Video: Calculating the Difference between Integers with Opposite Signs Mathematics

Video Transcript

The temperature inside a house is negative 14 degrees Fahrenheit, and the temperature outside is seven degrees Fahrenheit lower. What is the temperature outside the house?

We’re told in the question that the temperature inside the house is negative 14 degrees Fahrenheit. Outside, it is seven degrees lower. This means we need to subtract seven degrees Fahrenheit from negative 14 degrees Fahrenheit.

In order to subtract seven from negative 14, we can use a number line. We begin at negative 14 and move seven places to the left. This takes us to negative 21. So, negative 14 minus seven is negative 21.

We can, therefore, say that the temperature outside the house is negative 21 degrees Fahrenheit.