Which of the following equations has imaginary roots? x2 + 3x – 5= 0
22 – 7x + 10 = 0
2x2 – 3x + 1 = 0
22 +63 + 10 = 0

Arefrigeration system at your company uses temperature sensors fixed to read celsius (°c) values, but the system operators in your control room understand only the fahrenheit scale. you have been asked to make a fahrenheit (°f) label for the high temperature alarm, which is set to ring whenever the system temperature rises above –10°c. what fahrenheit value should you write on the label?