1) The LCM of 5 and 6 is the product of the two numbers (at least in this case). 5 * 6 is 30, so the LCM is 30. In other cases, you would look at the prime factorization of each number, take out what they have common, and then multiply.
2) To find the GCF of 14 and 35, we need to look at their prime factorizations. The prime factorization of 14 is 2 * 7, and the prime factorization of 35 is 7 * 5. Now we look at what is in both of the factorizations. 7 is in both of them, so the GCF is 7.
3) Here, we can use the distributive property. The distributive property says a(b + c) = a(b) + a(c). Now we can use this logic here. 3 * 5 is 15, and 3 * 6 is 18, so that it is equal to 15 + 18.
