In determining cost behavior in business, the cost function is often expressed as y = a + bx. Which one of the following cost estimation methods should not be used in estimating fixed and variable costs for the equation?

Answer (D) is correct. Regression analysis can be used to find an equation for the linear relationship among variables. However, multiple regression is not used to generate an equation of the type y = a + bx because multiple regression has more than one independent variable. In other words, a multiple regression equation would take the form y = a + b1x1 + b2x2 + b3x3 + . . . .