The equation 𝐶 equals negative five 𝐹 plus 160 over negative nine shows the relationship between the temperature 𝐹 in Fahrenheit and the temperature 𝐶 in Celsius. If in Alaska, the temperature is negative 22 degrees Fahrenheit, what is the temperature in degrees Celsius?
We’ve been given a formula that shows us degrees Celsius in terms of degrees Fahrenheit. And we know what the temperature in Alaska is in degrees Fahrenheit. To find the degrees Celsius, we take what we know about the degrees Fahrenheit and plug it in for 𝐹 in our equation. When we do that, we’ll have negative five times negative 22 plus 160 all over negative nine. Negative five times negative 22 is 110. We’ll bring everything else down. And we’ll have 110 plus 160 over negative nine, which is equal to 270 divided by negative nine, which is negative 30. We’re saying that negative 22 degrees Fahrenheit is equal to negative 30 degrees Celsius.