Serendipity Co. uses regression analysis to develop a model for prediction overhead costs. Two different cost drivers (machine hours and direct materials weight) are under consideration as the independent variable. Relevant data were run on a computer using one of the standard regression programs, with the following results.

Machine hours	Coefficient
Y intercept	2,500
B	5.0
r-squared = .70
Direct materials weight
Y intercept	4,600
B	2.6
r-squared = .50

Which regression equation should be used?

y = 2.500 + 5.0x y = 2500 + 3.5x y = 4,600 + 2.6x y = 4,600 + 1.3x