Given: Q = 7m + 3n, R = 11 - 2m, S = n +5, and T = -m - 3n + 8.
Simplify [Q - R] + [S - T].

Im gonna fail 7th grade selective breeding 1. creates offspring which are genetically identical to the parent 2. is the process of breeding only organisms with desirable traits 3. involves the removal of the nucleus of a cell 4. combines traits from organisms of different species

The difference between two numbers is one. three times the larger number minus two times the smaller number is 9. what are the two numbers

Can someone explain to me how to do