The measure of angle AEB is 19 degrees
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
It would be a. 8/9 because for every 8/9 boy, there is 1 girl. To check this work, you can do 8/9 x 18 which equals 16.
I’m 99% sure it’s D because you would add both those numbers to equal his debt that day
3(2m + 9) - 1 = 2
6m + 27 - 1 = 2
6m + 26 = 2
6m = 2 - 26
6m = -24
m = -4