What is the measure of the missing angle?

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?

Complete the solution of the equation. find the value of y when x equals to 6 4x+y=20

1.based of the diagrams what is the the value of x? 2.how would you verify your answer for x