Answer:
8 roses and 12 carnations.
Explanation:
For this question, we can use substitution.
r + c = 20, so r = 20 - c.
Substitute this into the second equation, and we get (0.75)(20 - c) + 0.5 c = 12
We can expand, getting 15 - 0.75c + 0.5c = 12.
Combine like terms, and we get 0.25c = 3.
We then solve for c: 12.
Plug this back into the first equation, and we get r = 8.
There are 8 roses and 12 carnations in Denny's bouquet.