A fruit seller sells apples for ₹30 each and bananas for ₹10 each. A customer has exactly ₹150 to spend.
(i) Write the linear equation in x (number of apples) and y (number of bananas) that represents this situation.
(ii) Plot the graph of this equation on the Cartesian plane, taking suitable scales.
(iii) Using the graph, determine whether buying 3 apples and 9 bananas is possible.