Step-by-step explanation:
Distance = rate × time
If B is the rate of the boat, and C is the rate of the current, then we can write two equations:
18 = (B + C) × 3
18 = (B − C) × 9
Simplifying the equations:
6 = B + C
2 = B − C
Add the equations together to eliminate C:
8 = 2B
B = 4
Plug into either equation to find C:
C = 2
The boat's rate is 4 mph, and the current's rate is 2 mph.
 
        
             
        
        
        
Answer:
see explanation
Step-by-step explanation:
(a)
Given y is directly proportional to x then the equation relating them is
y = kx ← k is the constant of proportion
To find k use the condition when x = 3, y = 18 , then
18 = 3k ( divide both sides by 3 )
6 = k
y = 6x ← equation of proportion
(b)
(i)
when x = 12 , then
y = 6 × 12 = 72
(ii)
when y = 42
42 = 6x ( divide both sides by 6 )
7 = x
 
        
             
        
        
        
Answer:
27,77
1 saatte 3600 saniye var
100 km de 100.000 metre yapar o halde 
100.000/3600 = 27,77 m/sn yapar
alıntıdır (◍•ᴗ•◍)
 
        
             
        
        
        
Answer:
It should I only looked at the first few columns and the matched up
Step-by-step explanation:
 
        
             
        
        
        
Answer:
b = -8
Step-by-step explanation:
6b = -42
Divide by 6 on both sides
b = -8