So firstly, you want to split the equation into the format of a^2 + bx + c, so you know what a, b and c equal. a = 1b = -7c = 12 Now, you need to try to split the equation into the format (x + ?)(x + ?). To work out what the question marks are, you need to find the two numbers that: Add up to -7Multiply to 12So this would by -3, and -4. Now you have your two question marks, you need to put them into your factorised equation, making sure you keep the correct symbols. So the correct answer would be, (x-3)(x-4).