Short-Run iso-Profit lines A$Iiso- profit line(等利润线) contains all the production plans that yield a profit level of $Il The equation of a sii iso-profit line is I≡py-W1X1-W2X2 Le II+W2X y x1+Short-Run Iso-Profit Lines A $ iso-profit line (等利润线) contains all the production plans that yield a profit level of $ . The equation of a $ iso-profit line is I.e.   py − w1 x1 − w2 x2 ~ . y w p x w x p = + 1 + 1  2 2 ~