rewrite 8r+8s as a distributive property
8(r + s)
The distributive property says that a(b + c) = ab + ac. Here, substitute, 8 for a, r for b and s for c for instant success.
Hi Elizabeth. Ralph already gave you a nice simple answer. But one way to remember this for good is by thinking through a simple example. If I asked you to solve 2(3+5), I am sure you would tell me - that easy! Just add the 3 and 5, so that becomes 2(8) = 16. But look at it again - a different way you can solve this is by "distributing" the 2 to the 3 and 5. This gives you 2(3) + 2(5) = 6 + 10 = 16. The example you give, 8r + 8s, which can be written as 8(r) + 8(s), is just the "backwards" working of the problem. We have to think - is there some common term we can "factor out" (the reverse of "distributing") of the given terms? Yes - in your case, 8. Factor out the 8, and rewrite what's left:
8r + 8s = 8(r) + 8(s) = 8(r+s).