Answer:
One rose bush = $3
One bunch of ornamental grass = $4
Step-by-step explanation:
We can set up a system of equations to solve for this. Let cost of 1 rose bush be r and cost of 1 ornamental grass be g. Thus we can form 2 equations:
![14r+7g=70\\5r+14g=71](https://tex.z-dn.net/?f=14r%2B7g%3D70%5C%5C5r%2B14g%3D71)
We can multiply the first equation by -2 so that we can eliminate g. Thus, we have:
![(*-2)14r+7g=70\\5r+14g=71\\-------\\-28r-14g=-140\\5r+14g=71\\--------\\-23r=-69\\r=\frac{-69}{-23}=3](https://tex.z-dn.net/?f=%28%2A-2%2914r%2B7g%3D70%5C%5C5r%2B14g%3D71%5C%5C-------%5C%5C-28r-14g%3D-140%5C%5C5r%2B14g%3D71%5C%5C--------%5C%5C-23r%3D-69%5C%5Cr%3D%5Cfrac%7B-69%7D%7B-23%7D%3D3)
Thus, 1 rose bush is $3. Now plugging in r = 3 into the first original equation, we can solve for g:
![14r+7g=70\\14(3)+7g=70\\42+7g=70\\7g=70-42\\7g=28\\g=\frac{28}{7}=4](https://tex.z-dn.net/?f=14r%2B7g%3D70%5C%5C14%283%29%2B7g%3D70%5C%5C42%2B7g%3D70%5C%5C7g%3D70-42%5C%5C7g%3D28%5C%5Cg%3D%5Cfrac%7B28%7D%7B7%7D%3D4)
Thus, 1 bunch of ornamental grass is $4.