The answer is 5 since the total is 7 and you already have 2
Answer:
The maximum number of volleyballs that she can buy is 19
Step-by-step explanation:
Let
x ----> the number of volleyballs
we know that
The cost of each volleyball net ($28) by the number of volleyball nets (4) plus the cost of each volleyball ($7) multiplied by the number of volleyballs (x) must be less than or equal to $250
so
The inequality that represent this situation is

Solve for x

subtract 112 both sides


Divide by 7 both sides

therefore
The maximum number of volleyballs that she can buy is 19
Substitute y=4x to the second equation:
x^2 + (4x)^2 = 17
x^2 + 16x^2 = 17
17x^2 = 17
x^2 = 17/17
x^2 = 1
x = 1 and -1
When x=1, y=4(1) = 4
When x=-1, y=4(-1) = -4
Thus the solutions would be (1,4) and (-1,-4). That would correspond to D. and A.