i got negative constant? how?

Answer the following questions 1 through 4 using the information below: The Connors Company has assembled the following data pertaining to certain costs that cannot be easily identified as either fixed or variable. Connors Company has heard about a method of measuring cost functions called the high- low method and has decided to use it in this situation. Cost $23,000 $22,120 $34,600 $42,000 $38,000 Machine Hours 5,000 6,450 7,650 10,000 9,350 1) What is the slope coefficient per machine-hour? 2) What is the constant? | 3) What is the cost function? 4) What is the estimate of total operating costs when 9,000 machine-hours are used? 5) The cost components of a picture frame include $.65 for the glass, $.75 for the wooden frame, and $.80 for assembly. Rent costs for this year will be $7,000.00. 1,000 frames are expected to be produced in the coming year. What cost function best represents these costs