Answer:
I cannot see the number line mentioned here, but I'll explain how you multiply negative and positive using tiles and number line.
To multiply positive and a negative nunber, for instance, 2(–3), you'll think of it as 2 groups of negative one in three's. Using tiles you have
–1 –1
–1 –1
–1 –1
Two groups of negative one in three's, adding that up we have 6.
Using number line. See 2(–3), for instance, as moving twice in intervals of –3. If I am to multiply that, starting from 0, if I move once, I'll land at –3, if I move one more time, I'll land at –6. Since I am to move twice, that's the required answer.