Answer:
Step-by-step explanation:
If we are given the quadratic model, we know that the height of anything on the ground is 0 meters, so that model becomes
I changed your x's to t's since t is for time.
Now we need to factor that quadratic and solve for time:

Since -2 definitely does not equal 0, then

Factor that and find t values of 4 and -2. Again, we know that time will never be negative, so
t = 4 seconds.
So first create and define your variables:
Z = amount of zebra fish
N = amount of neon tetras
Now create your equations:
2z+2.15n=31.20
z+n=15
This is your system. There are multiple methods to use but in this problem I’ll use the substitution method by simplifying the bottom equation.
2z+2.15n=31.20
z=15-n
Now I’ll plug the bottom equation into the top one.
2(15-n)+2.15n=31.20
And just solve from here.
30-2n+2.15n=31.20
0.15n=1.20
n=8
So he bout 8 neon tetras, and 15-8= 7, so he bought 7 zebra fish
The correct answer is B
To find the average we add all the given numbers together then divide by how many numbers there are.
A is 7
B is 8
C is 9
The answer is 26 because I added