check the picture below.
make sure your calculator is in Degree mode.
Using the proportion given, there will be 57 catfish in the pond.
The proportion given to us is
5.7/20 = x/200
Cross multiply:
5.7*200 = 20*x
1140 = 20x
Divide both sides by 20:
1140/20 = 20x/20
57 = x
no for a
yes for B
no for c
that what I think It is opinion could be wrong
Split it into 2 equations
2x-9 = 7
2x = 16
x = 8
And another equation
2x-9 = -7
2x = 2
x = 1
The answer is x =1, x= 8