Can I get help with this question

Idon’t understand! use slope intercept form to solve: through: (2,5) slope= undefined

Use the four functions below for this question. compare and contrast these four functions using complete sentences focus on the slope and y- intercept first, and then on any additional properties of each function

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a. m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?