Answer:
c.
Step-by-step explanation:
All of the things are correct with this one.
We can put the two equations together with substitution, and we get
3x + 2y = 30
Now we have a single equation in two variables, so we don't have enough information to solve for both x and y.
Answer:
7.5
Step-by-step explanation:
fourths mean 1/4
We will have to multiply the initial value with the 1/4
30 * 1/4 = 7.5