A part of the graph representing an electrical signal is shown. The voltage first rises steadily from an initial value (A) till a maximum value (B) and then drops instantly till to the initial voltage (at C) and this repeats, such that || and and are vertical. If A = (1, 1) and B = (4, 3) respectively, then what is the equation of ? -3y – 2x = 5 3y – 2x = 5 3y – 2x = 5 3y + 2x = 5