Lianne charged twice as much to walk a large dog than she did to walk a small dog. This week she had time to was 10 small dogs and 5 large dogs, and she wants to make $100. How much should she charge per small dog? Per large dog?

Well she charged twice as much to walk large then small. Let s be small and l be large.

We we know that

l = 2s

we also know that she wants to make 100 so

xl + ys = 100

Where where x is number of large and y is number of small. it says she walked 10 small and 5 large so

5l + 10s = 100

substitute 2s for l because they are same value as shown in first equation I made

5 (2s) + 10s = 100

10s + 10s = 100

20s = 100

s = 5

we can now solve for l

l = 2s

l = 2 * 5

l = 10

So s is 5 and l is 10.