Answer:
y=3
Step-by-step explanation:
Multiply 9 from both sides to cancel it out.
-27=-y/9
/9 /9
-3=-y
We can't have a negative variable, so we divide -1 from both sides.
-3=-y
/-1 /-1\
3=y
-hope it helps
Answer:

Step-by-step explanation:
The fish population after t years can be modeled by the following equation:

In which F(0) is the initial population and r is the constant rate of decay.
Year one the fish population was 18000
This means that 
In year three the fish population was 8000 fish.
Two years later, so 






So

Answer:
b
Step-by-step explanation:
The answer is a parallelogram
You mean -2x+5y=20 if it was that's how you do it
so if you're finding the x intercept the y will turn to 0 why because you're only looking for x their's no need for y
so it will be -2x+0=20
-2x=20 if it's multiplication then you change it to division
-2x/-2=20/-2
x=-10