Answer:

Step-by-step explanation:
see the attached figure with letters to better understand the problem
step 1
In the right triangle ACD 
Find the length side AC
Applying the Pythagorean Theorem

substitute the given values



simplify

step 2
In the right triangle ACD
Find the cosine of angle CAD

substitute the given values

 ----> equation A
 ----> equation A
step 3
In the right triangle ABC
Find the cosine of angle BAC

substitute the given values
 ----> equation B
 ----> equation B
step 4
Find the value of x
In this problem
 ----> is the same angle
 ----> is the same angle
so
equate equation A and equation B
 
 
solve for x
Multiply in cross


step 5
Find the length of BC
In the right triangle BCD
Applying the Pythagorean Theorem

substitute the given values



simplify

 
        
             
        
        
        
You first must find the 18% of the fish population.
You multiply 500 by .18 . You are supposed to get 90. 
90 is the 18% fish increase. 
Then you just add 500 + 90 and you will get 590 fish that are now in the school.
        
             
        
        
        
Ummm this confuses me a bit
        
             
        
        
        
Answer:
Step-by-step explanation:
 
        
             
        
        
        
Answer:
False
Step-by-step explanation:
the slope is -2/1 AKA -2 so it is negative