Market Equilibrium

Suppose your firm faces a demand curve as follows: Q ^d_x = 100 – 0.3P_X + 0.6P_Y + 0.03M where M is per capita income currently estimated at $22,000. P_Y is $400. At what price would your firm maximize its total revenues and what would that revenue be at that point? (Hint: Simplify the demand function by inserting the given values of P_Y and M. Then think about where TR is maximized. Remember that for this particular linear demand function, α_x = -0.3. Find price and TR.