Okay, so let's go over multiplying negative numbers. A positive times a positive is a positive, right? But a negative times a negative is also a positive. Only a negative times a positive (or a positive times a negative) gives you a negative number. So, we know that one of our 2 numbers in this question must be negative; the other must be positive.
Let's now take a look at the factors of -147, starting with the positives. Obviously, -147 and 1 are factors: -147 * 1 = -147. What other factors of -147 are there?
What about 7? Try it: -147 / 7 = -21. So here are two factors: -21, and 7. They multiply to -147. Do they add up to -14? Let's see: -21+7 = 7+(-21) = 7-21= -14. Yup, that works!
